How To Switch Between An eSIM & SIM For Calls On iPhone

Switching between an eSIM and a physical SIM on your iPhone is easier than you might think. Whether you want to separate your work and personal calls to improve your work-life balance, or just make the most of your iPhone’s dual-SIM capabilities, we’ve got you covered. Here’s your step-by-step guide to switching between SIMs for calls – plus a few handy tips for business owners.

Quick recap: What is an eSIM, and how is it different from a physical SIM?

A physical SIM is the little plastic card you insert into your phone. It connects your device to your mobile network provider, allowing you to make calls, send texts, and use mobile data. An eSIM is a digital version of that – it’s built into your device and stores your mobile plan without needing anything physical. No trays, no swapping, no losing tiny bits of plastic.

With an iPhone, you can use both a physical SIM and an eSIM at the same time – perfect if you want to run two numbers on one phone.

Still confused? Read our guide to what eSIMs are and how they work.

Why use eSIM and dual-SIM features for business?

There are loads of eSIM benefits that businesses should consider. With a dual SIM set up using eSIM, you can:

• Separate work and personal numbers easily without needing two phones.
• Simplify travel by adding local data plans via eSIM without removing your main SIM.
• Manage costs and usage by keeping work calls on one line and personal data on another.
• Switch flexibly between the two lines depending on your needs.

For business owners, it’s a smart, streamlined way to stay connected while keeping your work and personal lives neatly divided.

How to switch between an eSIM and SIM for calls on iPhone

Switching between eSIM and SIM on iPhone is straightforward, just follow these steps:

1. Tap Settings on your iPhone.
2. Scroll down and tap Mobile Service (or Cellular, depending on your region).
3. Tap Default Voice Line (it might also show as “Default Line” on some models).
4. You’ll see both your eSIM and physical SIM listed here. Tap the line you want to use for outgoing calls to select it.

Top tip: If you want to switch lines just for one call, you don’t need to change the default. When you dial the number, tap the small “Primary” or “Secondary” label above the number and pick the line you want.

Switch phone numbers for a call

You can also switch lines when calling someone from your Favourites or from the keypad. Here’s how to switch between your two phone numbers before you make a call:

From Favourites:

1. Tap the Info button next to the contact.
2. Tap the current phone number.
3. Choose your other number.

From the keypad:

1. Enter the phone number.
2. Tap the phone number near the top of the screen.
3. Select the number you want to use.

How iPhone remembers your choice for contacts

When you call a contact, your iPhone automatically remembers which line you used last time – and will use the same one again by default. If you haven’t called that contact yet, it will use your current Default Voice Line.

Want to change it manually? Just open the contact, tap the “Default” label under their name, and pick the number you want to use for future calls.

Receiving calls with Dual SIM

You can receive incoming calls on either your physical SIM or eSIM number. Your iPhone handles both lines automatically.

Important for business users: If you’re on a call using one line and you get an incoming call on your other number, you can answer it, as long as Wi-Fi calling is turned on and supported by your carrier. If not, the call will go to voicemail instead. You won’t get a missed call alert for the secondary number unless voicemail is set up.

How to temporarily disable an eSIM line

Need to pause one of your lines without deleting it? Here’s how to quickly disable your eSIM profile on iPhone:

1. Open Settings > Mobile Service (or Cellular).
2. Tap on the eSIM line you want to disable.
3. Toggle off Turn On This Line.

This disables the line without deleting it, so you can reactivate it later with one tap.

Troubleshooting: Common issues when switching lines

• Can’t see both SIMs?

Make sure both the physical SIM and eSIM are active. If you recently set up an eSIM, check that it’s installed correctly under Settings > Mobile Service.

• Calls not going through?

Double-check that the chosen line has a good signal. If you’re indoors or in a spotty area, one network might perform better than the other.

• Wrong number showing up for outbound calls?

Make sure you’ve selected the right default line, and double-check the individual contact settings. You can set a preferred line for each contact if you like.

Handy tips for business owners using dual SIMs on iPhone

• Label your lines clearly. Under Settings > Mobile Service, you can rename each line (e.g., “Work” and “Personal”) to avoid confusion.
• Set work hours. Consider using Focus modes (Settings > Focus) to control which line can notify you during work hours vs. downtime.
• Assign contacts to a specific line. You can set a default line for each contact, so calls to clients always go out from your work number.
• Keep an eye on data usage. If your work plan has data limits, you can set mobile data to use your personal line instead – or vice versa.

The takeaway

Switching between an eSIM and SIM for calls on iPhone is quick and simple – and with a little setup know-how, you can manage your business and personal calls like a pro. And with us, making the most of your business communication setup is simple, easy, and stress-free.

Get set up with a YourBusinessNumber eSIM today

Ready to take your business calls to the next level? With our service, getting your business eSIM is fast, simple, and fully automated. From the moment you complete your purchase, you’ll receive an activation email with your QR code and mobile number – ready to scan and connect straight away. Most customers are up and running within 15 minutes, with no SIM cards or postal delays to slow you down.

Whether you’re managing multiple team devices or just want a smarter way to separate work and personal calls, our business eSIM service keeps communication seamless and stress-free.

Not quite ready to switch fully to eSIM? No problem. Our virtual WhatsApp Business numbers offer an easy way to get started with professional business messaging – without needing a second phone or SIM card. It’s the perfect first step toward smarter, more flexible business communication.