Indian Phone Number Format Explained

Understanding the India phone number format is the first step for any US business that calls, texts, or supports customers and teams in India.

The rules are consistent once you know them. India uses the country code +91, a nationwide 10-digit national number, STD (Subscriber Trunk Dialing) codes for landlines, and a single time zone. This guide breaks down every part of the format and shows you exactly how to dial — from the US, from within India, and for business use.

For a step-by-step walkthrough focused only on placing the call, see our companion guide on how to call India from the US. This page is the reference for the number format itself.

What Is the Indian Phone Number Format?

An Indian phone number, written in full international form, looks like this: +91 XXXXX XXXXX. The +91 is the country code, and the ten X digits are the national number.

India is not part of the North American Numbering Plan (NANP), the system that covers the US, Canada, and much of the Caribbean under country code +1. India runs its own independent numbering plan under +91.

The national number after +91 is generally 10 digits. That length is consistent across the country, which makes Indian numbers easier to validate than numbers from countries with variable-length formats.

There are two broad categories of number inside that 10-digit space:

• Mobile numbers — always 10 digits, beginning with 6, 7, 8, or 9.
• Landline (fixed-line) numbers — an STD area code plus a local subscriber number that together total 10 digits.

The most important formatting concept in India is the leading 0. In domestic writing, landline area codes are shown with a leading 0 — for example, Delhi as 011 or Mumbai as 022. That 0 is the domestic trunk prefix. It tells the Indian network “this is a long-distance call to another city.” It is used only inside India and is always dropped when dialing from abroad.

So the same Mumbai landline can appear three ways depending on context:

• Local number only (within the same city): the 8-digit subscriber number.
• Domestic long-distance (from another Indian city): 022 followed by the 8-digit number.
• International (from the US): 011 91 22 followed by the 8-digit number.

The number never changes — only the prefix in front of it changes with distance. Keeping that idea straight resolves most confusion about Indian phone numbers.

There is also a standard machine-readable way to write an Indian number: E.164 format. E.164 is the international standard for phone numbers, and it looks like +91XXXXXXXXXX — the plus sign, the country code, and the national number, with no spaces, dashes, or leading 0.

E.164 is what phone systems, CRMs, and dialers prefer to store, because it is unambiguous from anywhere in the world. When you save an Indian contact as +91 plus the 10 digits, that entry works from a US mobile, from within India, and from any third country, without editing.

The spaced form you often see printed — +91 98XXX XXXXX for a mobile, or +91 22 XXXX XXXX for a Mumbai landline — is the same number formatted for human readability. The spaces are cosmetic; the underlying digits are what matter.

The India Country Code (+91)

India’s country code is +91, assigned by the International Telecommunication Union (ITU). Every phone number in India, mobile or landline, sits under this single code.

The + symbol is a universal placeholder for “the international access (exit) code of the country you are calling from.” It is not a digit you press directly on most landlines. Instead you replace it with the exit code of your own country.

From the United States, the exit code is 011. So +91 becomes 011 91 when dialed from a US landline. On a US mobile phone, you can enter the + directly (press and hold the 0 key), which lets you dial +91 without remembering 011.

India also has its own exit code for outbound international calls: 00. When someone standing in India calls the United States, they dial 00 1 followed by the US number. That 00 is the counterpart to America’s 011 — every country has its own exit code, and India’s is 00.

Here is how the country code combines with the rest of the number from different starting points:

Calling from	Prefix you dial	Then
US landline	011 91	10-digit Indian number (drop STD 0)
US mobile	+91	10-digit Indian number (drop STD 0)
Within India (mobile)	(nothing)	10-digit mobile number
Within India (other city landline)	0 + STD	local subscriber number

The single most common country-code mistake is writing +91 0 — combining the international country code with the domestic trunk 0. Those two prefixes are mutually exclusive. If you use +91 (or 011 91), the leading 0 disappears.

India City / STD Codes

Indian landlines use STD codes — Subscriber Trunk Dialing codes — which serve the same purpose as area codes in the United States. Each city or region has its own code, and its length varies: major metros use short 2-digit codes, while smaller towns use 3- or 4-digit codes.

Because the total national number is generally fixed at 10 digits, there is a trade-off: the shorter the STD code, the longer the local subscriber number, and vice versa. Delhi’s 2-digit code (11) leaves 8 digits for the local number. Jaipur’s 3-digit code (141) leaves 7 digits. Lucknow’s 4-digit code (522) leaves 6 digits.

The table below lists verified STD codes for major Indian cities. The “domestic” column shows the code as Indians write it (with the leading 0). The “from US” column shows what you dial after 011 91, with the 0 removed.

City	STD code (domestic)	Dial from US after 011 91
Delhi	011	11
Mumbai	022	22
Bangalore (Bengaluru)	080	80
Chennai	044	44
Kolkata	033	33
Hyderabad	040	40
Pune	020	20
Ahmedabad	079	79

Several other major cities use longer STD codes. These are equally common in business contact records, so it helps to recognize the 3- and 4-digit pattern:

City	STD code (domestic)	Dial from US after 011 91
Jaipur	0141	141
Lucknow	0522	522
Chandigarh	0172	172

Notice how the metro codes (Delhi, Mumbai, Bangalore, Chennai, Kolkata, Hyderabad) are the shortest. India assigned single- and double-digit trunk codes to its highest-volume centers, which is a common pattern in national numbering plans worldwide.

A practical tip for reading Indian landline numbers: if you see a landline written with a leading 0, that 0 is part of the STD notation and is never dialed internationally. Everything after the 0 — the STD digits plus the subscriber digits — is what you dial after the +91 country code.

It also helps to understand why STD codes vary in length. India assigns shorter trunk codes to regions with the highest call volumes and longer codes to smaller centers. This keeps the overall national number at a consistent length while still giving every locality a unique code.

So a two-digit STD code is a strong hint that you are looking at a major metro, while a three- or four-digit code usually points to a smaller city or town. Combined with the fixed 10-digit total, this lets you infer the local subscriber-number length just from the STD code.

For example, a number beginning 011 (Delhi) will have an 8-digit local part, while one beginning 0141 (Jaipur) will have a 6-digit local part. Both still add up to the same 10-digit national number once the STD code is included.

India Mobile vs Landline Numbers

The single biggest source of confusion in the Indian phone number format is telling mobile numbers apart from landlines. The rule is simple once you know the starting digit.

Mobile numbers are 10 digits and begin with 6, 7, 8, or 9. They do not use STD area codes. A mobile number is a self-contained block of 10 digits — you dial all of them, in order, with nothing in front except the country code when calling internationally.

Example of a mobile number in international form: +91 98XXX XXXXX. The leading 9 immediately signals “mobile.”

Landline numbers are the STD area code plus a local subscriber number. Together they generally make 10 digits. Landlines do not begin with the mobile prefixes; they begin with the area’s STD code.

Here is the structural difference laid out side by side:

Attribute	Mobile	Landline
Total digits (national)	10	10 (STD + local)
Starts with	6, 7, 8, or 9	STD area code
Uses an area code?	No	Yes
Leading 0 in domestic form?	Usually none	Yes (trunk prefix)
Dial from US	011 91 + 10 digits	011 91 + STD (no 0) + local

Mobile numbers usually have no leading 0 even in domestic writing, because they are not tied to a geographic trunk. When you save an Indian mobile contact, you typically store it as +91 plus the 10 digits, and it works from anywhere.

Landlines behave differently. Within the same city, a caller dials only the local subscriber number. To reach a landline in a different Indian city, the caller adds 0 plus the STD code. From abroad, the caller uses 011 91 (or +91) plus the STD code without the 0.

Because mobile penetration in India is extremely high, most business and personal contacts you deal with will be mobile numbers beginning with 6, 7, 8, or 9. Landlines remain common for offices, hotels, government departments, and established institutions, so it is still worth knowing the STD rules.

One more practical note on identification: if an Indian number you have been given is exactly 10 digits and starts with a 6, 7, 8, or 9, it is a mobile and needs no area code. If it starts with any other digit, or if it came with a leading 0 and a recognizable city code, it is a landline.

This starting-digit rule is also useful for validating data. If you import a list of Indian contacts and see a “mobile” number that starts with a 2, 3, 4, or 5, something is wrong — either the number is actually a landline whose STD code was mislabeled, or the leading digit was dropped or altered during entry.

For US teams building or cleaning a contact database, a simple check is worth automating: confirm each Indian number is 10 digits after the +91, and flag any “mobile” that does not start with 6, 7, 8, or 9. That single rule catches a large share of transcription errors before they turn into failed calls.

How to Dial India from the US

To call India from the United States, the pattern is:

011 + 91 + (STD code without leading 0) + landline number

or, for a mobile:

011 + 91 + 10-digit mobile number

Break it into four parts:

1. 011 — the US international exit code. Every international call from a US phone starts here. On a US mobile, press and hold 0 to enter +, which substitutes for 011.
2. 91 — India’s country code.
3. STD code or mobile prefix — for a landline, the STD code with its leading 0 removed; for a mobile, this is simply the first digits of the 10-digit number (no STD code needed).
4. The subscriber number — the remaining digits, so the national number totals 10.

Worked examples:

Target	Full sequence from a US phone
Delhi landline	011 91 11 xxxx xxxx
Mumbai landline	011 91 22 xxxx xxxx
Bangalore landline	011 91 80 xxxx xxxx
Indian mobile	011 91 98xxx xxxxx

The mobile case is the simplest: after 011 91, you dial all 10 digits of the mobile number exactly as they appear. There is no STD code to worry about and no 0 to drop.

The landline case has one rule to remember: drop the leading 0 from the STD code. A Delhi landline written domestically as 011-xxxx-xxxx becomes 011 91 11 xxxx xxxx from the US — the domestic trunk 0 is replaced by the 011 91 international prefix, and the STD code 11 follows.

If you are dialing from a US mobile, the whole thing simplifies to +91 plus the STD-without-0 (for landlines) or +91 plus the 10-digit mobile. Saving your India contacts in full +91 E.164 format is the most reliable approach, because the number then works whether you are in the US, in India, or anywhere else.

It is worth reinforcing the difference between the two exit codes involved. 011 is the US exit code, used when a call leaves the United States. 00 is the India exit code, used when a call leaves India. You use 011 to reach India from America, and someone in India uses 00 to reach America. They are not interchangeable.

This matters when you read numbers shared by Indian contacts. An Indian colleague may write their own number as 0 22 XXXX XXXX (domestic) or as +91 22 XXXX XXXX (international). Only the second form is ready to dial from the US. If you receive the domestic form, translate it: drop the leading 0 and prepend 011 91.

Text messaging follows the same addressing. To send an SMS to an Indian mobile from a US number, you use the same international format — +91 followed by the 10-digit mobile number — because SMS routing relies on the identical E.164 addressing that voice calls use.

How to Dial Within India

Dialing rules change once you are physically in India, because you are no longer crossing an international border.

Calling a mobile from anywhere in India: dial the full 10-digit mobile number. Mobile numbers are non-geographic, so there is no area code and no leading 0. This is the same whether the caller and the number are in the same city or opposite ends of the country.

Calling a landline in the same city: traditionally you dial just the local subscriber number without the STD code. Since you are already inside that city’s calling area, the network does not need the trunk code.

Calling a landline in a different city: dial 0 + STD code + local number. Here the leading 0 (the trunk prefix) is required. It signals a long-distance domestic call. For example, someone in Chennai calling a Delhi landline dials 0 11 followed by the 8-digit Delhi subscriber number.

Scenario (inside India)	What you dial
Mobile to mobile (anywhere)	10-digit mobile number
Landline, same city	local subscriber number
Landline, different city	0 + STD code + local number

This is exactly why the leading 0 exists and why it disappears for international calls. Inside India, the 0 tells the network “route this call to a different city.” From abroad, the international prefix +91 already handles that routing, so the 0 is redundant and must be omitted.

A helpful mental model: the leading 0 is a domestic long-distance signal. The +91 (or 011 91) is an international signal. You never need both, because you are either calling from inside India or from outside it — not both at once.

For a US employee traveling in India on a foreign SIM that is roaming, the safest habit is to dial every number in full +91 E.164 form. Roaming behavior can vary by carrier, and the international format sidesteps any ambiguity about whether the network is treating the call as domestic or international. It also means the same saved contacts work before, during, and after the trip without editing.

India Emergency Numbers

Emergency numbers are the same everywhere in India and are dialed without any STD code or country code. They are for use inside India and are not meant to be dialed internationally.

India’s unified national emergency number is 112. Modeled on the international standard, it connects a caller to police, fire, and medical response through a single point of contact. It is the number to remember if you can only remember one.

The older dedicated emergency lines remain active alongside 112:

Number	Service
112	Unified national emergency
100	Police
101	Fire
102	Ambulance
108	Emergency response / ambulance

100 reaches the police directly. 101 reaches the fire service. 102 is the ambulance line. 108 is widely used for emergency medical response and ambulance dispatch across many Indian states.

For a US business with staff traveling in India, the practical guidance is straightforward: 112 is the number to give employees, because it covers all emergencies and mirrors the single-number model travelers are used to. These numbers work from any Indian phone, including foreign SIMs roaming on Indian networks, and do not require a balance or an active plan.

India Toll-Free Number Format (1800)

India’s toll-free numbers begin with 1800, typically written as 1800 xxx xxxx. As with toll-free numbers in most countries, the called party (the business) pays for the call, and it is free for the caller.

Toll-free 1800 numbers are designed for domestic use inside India. They let Indian customers reach a company’s support or sales line at no charge from anywhere in the country, whether the caller is on a mobile or a landline and regardless of which city they are calling from.

There is an important limitation for US callers: a domestic Indian 1800 number is generally not reachable the standard way from outside India. Toll-free ranges are usually restricted to in-country origination. If you find an Indian company’s 1800 number and try to dial it from the US, the call will often fail to connect.

For that reason, businesses that want international customers to reach them typically publish an alternative — a standard +91 number, or, increasingly, a local number in the customer’s own country so the customer places what is effectively a domestic call. This is one of the strongest reasons US-facing companies adopt local virtual numbers, covered in the business sections below.

Indian Phone Number Format for Business

For a US business communicating with India — an offshore team, a vendor, or customers — the number format is only half the picture. The other half is time.

India observes a single time zone nationwide: India Standard Time (IST), UTC+5:30. Unlike the continental United States, which spans four zones, all of India — from Gujarat in the west to the northeast — runs on one clock. India also does not observe daylight saving time, so the offset never shifts with the seasons.

The half-hour offset (the :30) is what trips people up. IST is not a whole number of hours ahead of US zones — it is always an extra 30 minutes. Building that into your scheduling avoids missed meetings.

Here is the constant offset between IST and US time zones (US clocks do shift for daylight saving, so treat these as the standard-time relationship and adjust when the US is on daylight time):

US time zone	Approx. hours behind IST
Eastern (ET)	about 10.5 hours
Central (CT)	about 11.5 hours
Mountain (MT)	about 12.5 hours
Pacific (PT)	about 13.5 hours

The practical takeaway for scheduling: early morning on the US East Coast overlaps with the tail end of India’s business day. A call placed in the US morning reaches India in its late afternoon or evening. Later in the US day, India is already into the night. Because IST is a single, DST-free zone, once you learn your own offset it holds steady all year.

For a US company that regularly stores Indian contacts, the cleanest practice is to save every number in full E.164 format: +91 followed by the 10 digits, with no leading 0 and no spaces in the stored value. That format is unambiguous, works from any country, and is what most CRMs, dialers, and phone systems expect.

Common India Phone Number Mistakes

These are the errors that most often cause failed calls or misdialed numbers when working with Indian phone numbers.

Keeping the leading 0 when dialing internationally. Dialing 011 91 0 22 ... (with the 0 before the Mumbai STD code) is the number-one reason US-to-India landline calls fail. The domestic trunk 0 must be dropped once you use +91 or 011 91.

Adding an STD code to a mobile number. Mobile numbers are non-geographic and self-contained. Prefixing a mobile with a city STD code creates an invalid number. If it starts with 6, 7, 8, or 9 and is 10 digits, dial it as-is after +91.

Forgetting the 011 exit code from a US landline. A number shared online as +91 XXXXXXXXXX needs the + translated to 011 on a US landline: 011 91 XXXXXXXXXX. On a US mobile you can keep the +.

Wrong digit count. The Indian national number is generally 10 digits. If you are holding 9 or 11 digits, the number is likely mistyped, written in an old format, or still carrying a stray leading 0.

Trying to reach an Indian 1800 number from the US. Domestic Indian toll-free numbers usually will not connect from abroad. Ask the business for a +91 number or a local contact number instead.

Ignoring the half-hour time offset. IST is UTC+5:30, not a whole-hour offset, and India does not use daylight saving. Forgetting the extra 30 minutes — or assuming India shifts clocks like the US — is a frequent cause of mistimed calls.

Mixing +91 and 0 together. You never use both the international country code and the domestic trunk 0. Pick one based on where you are calling from: +91 (or 011 91) from abroad, or 0 + STD from another Indian city.

Avoiding these seven mistakes covers the overwhelming majority of India dialing problems for US teams.

Calling India from the US for Business

If your company calls India often — supporting customers, coordinating an offshore team, or managing vendors — the mechanics of per-call international dialing quickly become a distraction. A business phone system built for this removes the friction.

A virtual US phone number gives your team a single, professional identity that works regardless of where individual employees sit. Calls to and from India route through the same system your US operations already use, so there is no juggling personal phones or memorizing exit codes on every call. Learn more about how these numbers work on our virtual phone number page.

DialPhone provides virtual US phone numbers, including both local and toll-free US numbers, on plans that start at $24 per user per month. If you are consolidating existing lines, DialPhone offers free number porting, so you can bring your current business numbers across without disruption.

For teams handling inbound volume across time zones — including calls that arrive during India’s business day while your US office is closed — DialPhone’s AI receptionist can answer, route, and triage calls automatically. That matters for US-India operations specifically, because the 10.5-plus-hour offset means someone is almost always awake on one side of the relationship.

The reverse scenario matters too. Because domestic Indian 1800 toll-free numbers generally do not reach US callers, and because international dialing is a barrier for customers, giving your Indian-facing operation a clean, callable business number simplifies contact for everyone.

Consolidating US-India communication onto one system also cleans up your contact data. When every Indian number is stored in consistent +91 E.164 format inside a single platform, click-to-dial works reliably, call logs are accurate, and no one on the team has to remember whether to add 011 or drop a leading 0.

That consistency compounds as a team grows. A five-person sales desk calling Indian prospects, or a support group covering Indian customers overnight, benefits from a shared number and shared call history far more than from a collection of individual mobile phones with ad-hoc international dialing.

Ready to set this up? Review plans and features on the DialPhone pricing page, and if you need a US area code for a specific city or market, browse the full area codes directory to choose the right local number.

India vs US Phone Format Comparison

Putting the two systems side by side makes the differences clear. The US and India run entirely separate numbering plans, and the contrasts explain most of the dialing rules covered above.

Feature	India	United States
Country code	+91	+1
Exit code (calling out)	00	011
National number length	generally 10 digits	10 digits
Numbering plan	independent (ITU +91)	NANP (+1)
Area / trunk code	STD code, variable length, leading 0 domestically	3-digit area code, no leading 0
Mobile vs landline	mobiles start 6/7/8/9; no area code on mobiles	same 10-digit format for both; area code always used
Domestic long-distance prefix	0 + STD code	1 + area code
Toll-free prefix	1800	800, 888, 877, 866, 855, 844, 833
Time zones	one (IST, UTC+5:30)	multiple (ET/CT/MT/PT and more)
Daylight saving	not observed	observed in most states
Unified emergency number	112	911

A few contrasts stand out for US teams:

The 0 vs 1 trunk prefix. India uses a leading 0 for domestic long-distance; the US uses a leading 1. Neither is used when dialing internationally — the country code replaces it.

Mobiles and area codes. In the US, every number, mobile or landline, carries a 3-digit area code. In India, mobiles have no area code at all, while landlines do (the STD code). This is why a US phone number always has a recognizable area code and an Indian mobile does not.

Time. The US spans several time zones and shifts for daylight saving. India is one zone, at a half-hour offset, and never shifts. For scheduling recurring calls, India is actually the simpler side of the equation once you learn your offset.

Understanding both formats side by side is the fastest way to stop second-guessing how to write, store, and dial numbers across the US-India relationship.

Frequently asked questions

What is the India phone number format? +

The India phone number format uses the country code +91, followed by a 10-digit national number.

Mobile numbers are 10 digits and begin with 6, 7, 8, or 9. Landline numbers combine an STD (Subscriber Trunk Dialing) area code with a local subscriber number, and the two together generally total 10 digits. When written for domestic use, STD codes carry a leading 0 that is dropped when dialing from outside India.

What is India's country code? +

India's country code is +91. When you dial India from the United States, you first dial the US exit code 011, then 91, then the 10-digit Indian number.

On a US mobile phone, the plus sign replaces 011, so you can dial +91 directly. India's own exit code — used when someone in India calls out to another country — is 00.

How many digits is an Indian phone number? +

An Indian national number is generally 10 digits. Mobile numbers are always 10 digits and start with 6, 7, 8, or 9.

Landline numbers are the STD area code plus the local subscriber number, which together also add up to 10 digits. So a Mumbai landline uses the 2-digit STD code 22 followed by an 8-digit local number, while a Jaipur landline uses the 4-digit STD code 141 followed by a 6-digit local number.

What is the STD code for Delhi and Mumbai? +

Delhi's STD code is 011 and Mumbai's STD code is 022 in domestic format. Bangalore is 080, Chennai is 044, Kolkata is 033, and Hyderabad is 040.

The leading 0 is India's domestic trunk prefix. When you call these cities from the US, you drop that 0 — so Delhi becomes 11 and Mumbai becomes 22 after the 011 91 international prefix.

How do I call India from the US? +

To call India from the US, dial 011 + 91 + the STD code without its leading 0 + the landline number, or 011 + 91 + the 10-digit mobile number.

Example for a Delhi landline: 011 91 11 xxxx xxxx. Example for a mobile: 011 91 98xxx xxxxx. On a US mobile you can press and hold 0 to enter + and dial +91 instead of 011.

Do Indian mobile numbers have an area code? +

No. Indian mobile numbers do not use STD area codes. A mobile number is a self-contained 10-digit number that begins with 6, 7, 8, or 9.

STD codes apply only to landlines. This is why you dial an Indian mobile as all 10 digits directly after +91, with no area code and no leading 0 in front of it.

What is the emergency number in India? +

India's unified national emergency number is 112. It connects to police, fire, and medical response through a single line.

The older dedicated numbers still work as well: 100 for police, 101 for fire, and 102 for ambulance. 108 is used for emergency response and ambulance services in many states. These numbers are for use inside India and are not dialed internationally.

What does an India toll-free number look like? +

India toll-free numbers begin with 1800, in the format 1800 xxx xxxx. They are free to call from within India.

From outside India, a 1800 number is generally not reachable the same way, so businesses that want US callers to reach them typically publish a standard +91 number or a local number in the caller's country instead.

What time zone is India in? +

India observes a single time zone nationwide: India Standard Time (IST), which is UTC+5:30. The half-hour offset is unusual compared with most whole-hour zones.

Because the entire country uses one time zone and does not shift for daylight saving, the offset from US time zones stays constant year-round — a useful fact when scheduling recurring calls with India.