# eSIM or physical SIM for a device?

> When an eSIM delivered as a QR code is the quicker choice for a device, when a physical SIM is still the right one, and how to tell what yours supports.

Choosing a SIM · 18 December 2025

ThingSIM sells both at the same price, £2.00 per SIM, once. The choice comes down to what your device supports and how quickly you need it working.

## What each one is

A **physical SIM** arrives as a trio card, so you can pop out the mini, micro or nano size your device takes. It is posted to UK and EU addresses.

An **eSIM** is a profile downloaded onto a chip already built into the device. ThingSIM delivers it as a QR code minutes after you order, so there is nothing to post and nothing to insert. It is billed the same way as a physical SIM: nothing until you switch it on.

## Does your device support eSIM?

This is the deciding question, and the device decides it, not the SIM. Look for:

- "eSIM" or "eUICC" in the specification sheet
- An option in the device's settings or app to add a mobile plan by scanning a QR code or entering an activation code
- No SIM tray at all, which usually means eSIM only

Many routers, trackers and industrial devices still take only a physical SIM. Many newer devices take either. If the specification does not mention eSIM, assume physical.

## When each one is the better choice

| Situation | Better choice |
|---|---|
| Device has no SIM tray | eSIM |
| You need it working today | eSIM, delivered in minutes |
| Device is sealed or hard to open on site | eSIM, if supported |
| Device only takes a physical SIM | Physical |
| You are preparing many devices on a bench | Either; eSIM avoids handling cards |
| You want to swap the SIM to another device by hand | Physical |

## Moving a SIM between devices

A physical SIM moves with the card: take it out, put it in the new device. An eSIM profile lives on the device's chip, so moving service to a new device means installing a profile on that device. Plan for that if devices are swapped often in the field. The [guide to activating, pausing and moving SIMs](/activating-pausing-moving-sims) covers both.

## Developers

eSIM activation codes are available through the API as well as the portal (`GET /v1/iot/sims/{iccid}/esim`), so a production line or provisioning script can fetch a code and load it without anyone scanning a QR code. See [activating SIMs with the API](/activate-sims-with-the-api).

## Common questions

### Does an eSIM cost more than a physical SIM?

No. Both are £2.00 per SIM, once, and both are billed only from the day they are switched on.

### How quickly does an eSIM arrive?

As a QR code minutes after you order, so a device can be connected the same day.

### Can I get a physical SIM in the size my device needs?

Yes. Physical SIMs come as a trio card, so you pop out mini, micro or nano to suit the device.

## Recommended plan

250 MB, UK 4-network: £1.20 a month per active SIM, ex VAT.

Source: https://thingsim.com/esim-or-physical-sim