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What Is an eSIM and How Does It Work? (Explained for Businesses)
An eSIM is a SIM card built into a phone's hardware. Instead of inserting a plastic card, you download a mobile plan — an eSIM profile — by scanning a QR code or tapping an install link. Travellers use eSIMs to get local data abroad in minutes, and businesses resell them as an instant digital product.
In this article
An eSIM (embedded SIM) is a small chip soldered inside a phone, tablet or smartwatch that does the job of a traditional SIM card. The difference is that the mobile plan isn't printed on a piece of plastic — it's downloaded to the chip.
How an eSIM works
- The eSIM chip is built into the device. Each one has a unique ID called the EID.
- A mobile plan is packaged as an eSIM profile and stored on a secure provisioning server (an SM-DP+).
- The user scans a QR code or taps an install link. The phone contacts the server and downloads the profile.
- The profile appears as a new line in the phone's settings, ready to use for data.
A phone can store several eSIM profiles at once and switch between them — which is why travellers can keep their home number while using a local data plan abroad.
eSIM vs physical SIM
| Physical SIM | eSIM | |
|---|---|---|
| Delivery | Shipped or bought in a shop | Downloaded in minutes |
| Swapping | Remove and insert a card | Switch in settings |
| Multiple plans | One per slot | Several stored at once |
| Risk of loss | Can be lost or damaged | Nothing to lose |
| Travel | Find a local SIM shop on arrival | Install before you leave |
For a deeper comparison including pocket Wi-Fi, read eSIM vs physical SIM vs pocket Wi-Fi.
Why travellers love eSIMs
- No airport queues — install before departure, connect on landing
- Avoid roaming bills — prepaid local data is usually far cheaper than roaming (eSIM vs roaming)
- Keep WhatsApp and the home number — the main SIM stays active for calls and texts if needed
- Multi-country plans — one eSIM for a whole region
Which devices support eSIM?
Most recent flagship and mid-range phones do: iPhone XS and newer, Google Pixel 3 and newer, Samsung Galaxy S20 and newer, and many others. The phone must also be carrier-unlocked to use eSIMs from other providers. Our eSIM compatibility guide lists the details.
Why eSIM is a business opportunity
Because an eSIM is digital, it's an ideal product to sell online:
- Instant delivery — no stock, no shipping
- Global demand — every international traveller with a compatible phone
- Repeat sales — top-ups and the next trip
- Easy bundling — add it to flights, hotels, tours or memberships
With a white-label platform like Fully Signal, any business can sell eSIM data under its own brand. Learn what a white-label eSIM is.
Key terms in one minute
- EID — the eSIM chip's unique identifier
- ICCID — the identifier of an individual eSIM profile
- SM-DP+ — the server that stores and delivers eSIM profiles
- Activation code — the string encoded in the QR code
- Data-only eSIM — a plan with mobile data but no local phone number (explained)
See the full eSIM glossary for 40 more terms.
FAQ
Is an eSIM the same as a virtual SIM?
Not exactly. An eSIM is a physical chip inside the device that stores downloadable profiles. "Virtual SIM" is sometimes used loosely for app-based numbers, which are a different thing.
Can I use an eSIM and a physical SIM at the same time?
On most dual-SIM phones, yes. Many travellers keep their home SIM for calls and texts and use a travel eSIM for data.
Is eSIM safe?
Yes. eSIM profiles are downloaded over encrypted connections from secure provisioning servers, and there's no physical card that can be stolen and moved to another phone.
Can an eSIM be moved to a new phone?
It depends on the provider and the phone. Many travel eSIMs are designed to be installed once, so customers should install them on the phone they'll travel with.
