How keep Indian number active for OTPs while using a travel eSIM?

Traveling internationally from India presents a common challenge:

How do you get affordable mobile data without losing access to One-Time Passwords (OTPs) sent to your Indian number? The answer lies in the dual-SIM feature of modern smartphones. By pairing your Indian SIM with a travel eSIM, you can keep your Indian number active for receiving crucial SMS like OTPs while using affordable local data at your destination.

This guide covers everything from pre-travel prep to setup on arrival, so you can stay connected and secure without overspending.

Why is keeping your Indian number active for OTPs essential while traveling?

Your Indian phone number is more than just a number; it's a key to your financial and digital life. Losing access to it while traveling, even for a short time, can lock you out of critical services when you're most vulnerable.

Since so many services rely on SMS verification, keeping that number active abroad isn't just a convenience; it's a necessity.

The critical role of OTPs for banking and app security abroad

OTPs are the foundation of two-factor authentication for most Indian services. When you're abroad, you'll still need to manage your Indian bank accounts for things like transferring money or approving card payments.

Almost every one of these transactions requires an OTP sent only to your registered Indian mobile number. If you can't receive those texts, you can't manage your money.

It's not just about banking, either. You need that number for logging into government apps like DigiLocker, verifying your Aadhaar details, or even securing your email and social media accounts.

The challenge: Balancing affordable travel data with essential SMS access

The primary concern for travelers is cost. Using your Indian SIM for data roaming overseas can lead to extreme bills, sometimes thousands of rupees for just a little data. A travel eSIM, however, provides data for a fraction of the price. This forces a tough decision: either pay a premium to keep your Indian SIM active for data just to get OTPs, or use an affordable travel eSIM and lose access to those critical texts.

The ideal solution gives you the best of both: affordable data for browsing and reliable access to your Indian number for messages.

How does the dual-SIM and eSIM system work to solve this problem?

The dual-SIM and eSIM technology in most modern smartphones offers a clean solution to this travel problem. This feature lets your phone run two different mobile plans at the same time. By giving each plan a specific job, you can build an affordable and effective communication system for your trip.

Understanding the two-line strategy: Indian SIM for OTPs, travel eSIM for data

The strategy is straightforward: your phone operates with two active lines.

Line 1 (your Indian SIM) is for receiving calls and, crucially, SMS messages with your OTPs by connecting to a local network, but its data will be switched off to prevent high roaming fees.

Line 2 (your travel eSIM) becomes your main line for all mobile data, letting you use the internet, maps, and VoIP apps like WhatsApp at affordable local prices.

This setup guarantees you won't miss an important bank alert and also protects you from a massive data roaming bill.

The fundamental requirement: Activating international roaming on your Indian SIM

This is the one step you absolutely cannot skip. Your Indian SIM won't connect to any foreign network—meaning no SMS—unless you have activated an international roaming pack with your Indian provider before you fly. Just having a regular prepaid or postpaid plan isn't enough. Without a specific roaming pack, your SIM will be inactive overseas, and this whole setup won't work. All major carriers like Airtel, Jio, and Vi have special packs for this purpose.

Why a travel eSIM cannot receive OTPs for your Indian number

Many people wonder if a travel eSIM can receive their OTPs, but the answer is no. An OTP is a security feature locked to a specific phone number—in this case, your Indian number. A travel eSIM is a completely different product with its own temporary line.

There is no way to forward OTPs from your Indian number to a travel eSIM. The only way to get them is to keep your original Indian SIM active and able to receive texts while you're traveling.

What are the essential steps to prepare before you leave India?

A smooth trip starts with getting your phone ready before you leave. Taking care of a few things while you're still in India will prevent a lot of stress and trouble when you land.

Step 1: Activate an international roaming pack on your Indian SIM (Airtel, Jio, Vi)

Before you leave, you need to get an international roaming pack from your Indian provider, whether it's Airtel, Jio, or Vi. You can usually do this right from their app, website, or by visiting a store. Make sure you pick a pack that specifically mentions free incoming SMS. Many basic roaming plans are built for this, letting you receive OTPs without getting charged for each one. Don't skip this step—your SIM won't work overseas without it.

Step 2: Purchase and install your chosen travel eSIM

While you're still in India with good internet, find and buy a travel eSIM for your destination. Plenty of global providers sell them online. Once you buy it, you'll get a QR code by email. Just go to your phone's cellular settings, tap "Add eSIM," and scan the code to install it. It's best to install the eSIM before you leave but wait to activate it until you land so the plan's validity starts at the right time.

Step 3: Ensure your prepaid account has a sufficient balance or your postpaid plan is ready

If you're a prepaid user, buying a roaming pack isn't the only step. You also need to make sure you have enough main balance on your account to keep the SIM active and cover any small, unexpected charges. Incoming SMS might be free with the pack, but the account needs to be valid. For postpaid users, just confirm international roaming is active on your plan and your bills are paid up to prevent any service interruptions.

How should you configure your smartphone upon arrival at your destination?

As soon as you land, it's time to set up your phone to use both lines correctly. You'll need to go into your settings and assign the right jobs to your Indian SIM and your travel eSIM.

Getting these steps right is how you'll get affordable data while making sure your OTPs still come through.

Setting your travel eSIM as the primary line for mobile data

The very first thing to do is change where your phone gets its mobile data. Go into your phone's cellular or SIM settings, where you'll see both of your lines.

Find the "Mobile Data" or "Cellular Data" option and select your new travel eSIM as the primary source. This tells your phone to use the affordable travel plan for all internet activity, like browsing, maps, and apps.

Designating your Indian SIM for calls and SMS to receive OTPs

Now, let's configure your Indian SIM. In the same settings area, make sure that line is switched on and has connected to a local network. You can make it your default for calls if you want, but its real job is just to be active for receiving texts.

Critically, find the "Data Roaming" switch for your Indian SIM and make sure it is turned OFF.

This is the key to preventing your phone from using your Indian SIM for data, which saves you from huge roaming bills while it waits for OTPs.

A step-by-step guide for iPhone and Android cellular settings

The exact menu names might differ slightly, but the steps are basically the same for both iPhones and Android phones.

For iPhone:

• Go to Settings > Cellular
• Under Cellular Plans, check that both your Indian SIM (Primary) and travel eSIM are on
• Tap CellularData and select your travel eSIM
• Tap on your Indian SIM (Primary) and confirm the Data Roaming switch is OFF

For Android:

• Go to Settings > Network & Internet > SIMs
• You'll see both SIMs; tap each one to make sure they are active
• In the main SIMs menu, find Mobile data and set it to your travel eSIM
• Tap on your Indian SIM and make sure the Roaming switch is OFF

What if your phone only supports one SIM card?

Even though most new phones are dual-SIM, many people still use older models that only take one SIM card. This makes things tricky, but you don't have to choose between affordable data and getting your OTPs. You have two good workarounds.

The secondary phone solution: Using an older device just for your Indian SIM

The easiest and most dependable option is to bring a second phone. Simply use a spare smartphone you have available. After activating an international roaming pack, put your Indian SIM card into this backup phone. Keep it charged and on, but make sure both mobile data and data roaming are turned off. It will then act as your dedicated device for receiving OTPs, while your main phone uses a travel SIM or eSIM for all your data.

Converting your physical Indian SIM to an eSIM to free up the physical slot

If your single-SIM phone is eSIM-compatible, you have a sleeker choice. Before your trip, contact your Indian provider (Jio, Airtel, or Vi) and ask them to convert your physical SIM to an eSIM. This usually involves sending a quick SMS and then scanning a QR code they send you. Once your Indian number is digital, your physical SIM slot is now empty. You can insert a physical travel SIM for your destination into that slot, turning your phone into a dual-SIM device.

But of course, this option is a bit more challenging as you will need to actively look for a physical SIM card as soon as you land.

How can you avoid unexpected charges and common mistakes?

Using a dual-SIM setup abroad correctly requires paying attention to the details. One wrong setting can lead to surprisingly high bills. Knowing the common mistakes and following a couple of key rules will help you avoid any trouble.

The golden rule: Turn off mobile data for your Indian SIM

This is the most important rule for avoiding a huge bill. Go into your phone's settings and manually turn off "Mobile Data" and "Data Roaming" for your Indian SIM. Don't just assume that selecting the travel eSIM for data is enough; you need to disable data on the Indian line itself. Even tiny amounts of background data used by apps can cost a fortune at international roaming rates. Check this setting when you land and again periodically during your trip.

Understanding the costs associated with international roaming packs

An international roaming pack is essential, but it isn't free. The packs vary in price, how long they last, and what they include. Before you buy one, read the fine print on your provider's website carefully. Look at the cost, the validity (e.g., 10 days, 30 days), and what you actually get. The most important thing to check is that the incoming SMS is free. While some plans might include a few calling minutes or a small amount of data, your main goal is to get a plan that lasts for your whole trip and gives you free incoming texts for OTPs.

Why you must never delete your Indian SIM or eSIM profile while traveling

While adjusting settings, you might think about disabling or even deleting your Indian SIM or eSIM profile. Don't do it. Deleting the SIM profile cuts off all connection to your Indian number, which means you won't get any calls or texts—including your OTPs. Trying to reactivate an eSIM while you're overseas is extremely difficult, as it often requires a verification text sent to the very number you just turned off. Always keep your Indian SIM profile active on your phone.