You're staring at your phone screen. You have a number for someone in Delhi or Bangalore, but it just won't go through. It's frustrating. Honestly, the india country code phone system isn't actually that complicated once you strip away the confusing prefix rules that vary depending on where you are calling from.
India uses +91. That is the magic number.
But just knowing those two digits isn't always enough to get a WhatsApp message delivered or a voice call connected. If you’re dialing from a landline in the US, it looks different than dialing from a mobile in Dubai. If you're trying to reach a "toll-free" number in Mumbai from London, you're probably going to fail. There are layers to this.
The Basics of +91 and Why it Matters
The International Telecommunication Union (ITU) assigned +91 to India decades ago. It's the country's digital handshake. When you see a phone number starting with +91, you're looking at a 12-digit string that identifies a specific device among the 1.2 billion connections currently active in the country.
Most people get tripped up by the "0."
In India, if you are calling a number within the country from another Indian state, you often prefix it with a 0. However, when you use the india country code phone prefix of +91, you must drop that zero. It’s a binary choice. You either use the internal trunk prefix (0) or the international country code (+91). You can't use both. If you try to dial +91 098..., the call will likely drop or give you a busy signal.
Mobile numbers in India are almost always 10 digits long. They typically start with 6, 7, 8, or 9. If you see a number starting with a 5 or a 4, it's likely a specialized service or a paginating relic, though those are increasingly rare.
How Dialing Changes Based on Your Location
If you're in the United States or Canada, your exit code is 011. To reach India, you would dial 011-91, followed by the 10-digit mobile number.
Mobile phones have made this easier.
On a smartphone, you just hold down the '0' key until it turns into a '+'. This + symbol automatically replaces whatever exit code your current country uses. It’s a lifesaver for travelers. I've seen people try to memorize exit codes for every country they visit, but honestly, just use the '+' sign. It works in the UK (where the exit code is 00), it works in Australia (0011), and it works in Japan (010).
Landlines are a bit more rigid. If you are sitting in a hotel in London trying to call a business partner in Chennai, you have to dial 00-91-44... wait, what is the 44?
That's the area code.
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Landlines vs. Mobiles: The Great Divide
India’s landline system is structured differently than its mobile network. While mobile numbers are 10 digits, landlines are a combination of an area code (STD code) and the subscriber number. Together, they always total 10 digits.
- Delhi: The area code is 11. A landline looks like +91-11-XXXX-XXXX.
- Mumbai: The area code is 22. It looks like +91-22-XXXX-XXXX.
- Kolkata: The area code is 33.
- Smaller towns: These might have 3 or 4-digit area codes. For example, Agra is 562. In that case, the subscriber number is only 7 digits to keep the total count at 10.
When you're using the india country code phone format for a landline, the rule about the zero still applies. Locals call it an "STD code." If they give you a number like 022-2555-1234, and you are calling from outside India, you ditch that first zero. It becomes +91-22-2555-1234.
WhatsApp and the Digital Sync
WhatsApp is the lifeblood of Indian communication. If you don't have a contact's number saved correctly with the india country code phone prefix, they simply won't show up in your contact list.
This is the most common "tech support" issue people have when dealing with Indian counterparts. They save the number as 9810-XXXXXX. WhatsApp looks at that and thinks it's a local number for whatever country you are in. If you're in the US, WhatsApp assumes it's a US number and fails to find the account.
You must save it as +91 9810XXXXXX. No spaces. No dashes. Just the plus, the code, and the ten digits.
Interestingly, India’s Department of Telecommunications (DoT) recently implemented stricter Know Your Customer (KYC) norms. This means that if you're trying to call an Indian number and it says "out of service," it might not be a technical error. The government has been disconnecting millions of SIM cards that weren't properly verified or were linked to fraudulent activity. If a contact suddenly disappears, that could be why.
The Mystery of Toll-Free Numbers
Here is a bit of nuance: You generally cannot call an Indian 1800 number from outside India.
Indian toll-free numbers are designed for domestic use. If you are in New York and try to dial +91-1800-XXX-XXXX, it usually won't connect. These numbers are toll-free for the caller within India, but international carriers don't have an agreement to handle those costs.
If you need to reach an Indian bank or airline from abroad, look for their "International Subscriber" number. This is usually a standard landline in Mumbai or Delhi (+91-22... or +91-11...). It will cost you international rates, but at least the call will actually go through.
Future Changes: The 11-Digit Shift?
For years, there has been talk in the Telecom Regulatory Authority of India (TRAI) about moving to 11-digit mobile numbers. With a population of 1.4 billion and people owning multiple SIMs for different data plans, India is running out of 10-digit combinations.
So far, they've avoided this by reclaiming old numbers and opening up new prefixes (like those starting with 6). But eventually, the india country code phone format might have to accommodate an extra digit. If that happens, it won't change the +91 code, but it will definitely break a lot of automated systems and contact lists worldwide.
Common Errors to Avoid
Don't use the IDD (International Direct Dialing) code if you have the '+' sign.
Don't add a 0 before the mobile number.
Don't assume a 1-800 number will work from your country.
Do check the time zone. India is GMT+5:30. They don't do Daylight Savings Time. If you're calling from New York, they are 9.5 or 10.5 hours ahead of you.
Actionable Steps for Success
- Always use the '+' symbol on your smartphone. It bypasses the need to know your own country's exit code.
- Verify the number length. After the +91, there should be exactly 10 digits. If you have 11 or 9, the number is wrong.
- Ditch the trunk prefix. If the number you were given starts with a 0, delete it before adding +91.
- Save for WhatsApp immediately. Save the contact as +91XXXXXXXXXX to ensure they sync with encrypted messaging apps.
- Use VOIP for landlines. If you need to call an Indian landline and want to save money, use a service like Skype or Google Voice. Just ensure you select "India" from the dropdown so it automatically applies the +91.
If you follow these steps, your calls to the subcontinent will connect on the first try. The system is built for massive scale, and while it feels complex, it's actually remarkably consistent once you understand the +91 rule.