What is an ICCID?
An ICCID is the 19 or 20 digit serial number of a SIM, physical or eSIM. Here is what it identifies, where to find it on your phone, and why support asks for it.
An ICCID (Integrated Circuit Card Identifier) is the serial number of a SIM. Every SIM has one, whether it is a plastic chip or an eSIM profile downloaded onto your phone, and it is the number support will ask for when something goes wrong.
What it identifies
The ICCID identifies the SIM itself, and nothing else. It does not identify you, and it does not identify your phone.
That distinction matters, because phones carry three numbers that look alike:
- ICCID: the SIM. Changes when you install a different eSIM.
- EID: the eSIM chip soldered into the phone. Never changes.
- IMEI: the phone. Never changes.
If you install three travel eSIMs over a year, you have three ICCIDs, one EID and one IMEI.
How it is built
An ICCID is 19 or 20 digits and is read in parts:
- it starts with 89, which is the industry code for telecommunications, so every ICCID in the world begins the same way
- then a country code, then a code for the issuer, which is the operator or the provider that produced the profile
- then the serial number of that individual SIM
- the last digit is a check digit, calculated from the others, so a mistyped ICCID can usually be detected without asking the network
This is why the first few digits of two eSIMs bought from the same provider look identical. They are not duplicates, they are the same issuer.
Where to find it
On iPhone: Settings, General, About, then scroll to the section for the line you want. Each installed eSIM has its own block with its own ICCID.
On Android: Settings, About phone, SIM status, or Settings, Connections, SIM manager, depending on the manufacturer.
In both cases you can tap and hold to copy it, which is worth doing rather than reading twenty digits aloud.
Why support asks for it
When an eSIM is not connecting, the provider needs to look up the exact profile on the network. Your email address identifies your account, which may hold several eSIMs; the ICCID identifies which one.
It is also how a provider checks whether a profile has actually been installed on a device, has been used, or is still sitting undelivered. Sending it in your first message usually saves a round trip.
Sharing an ICCID with your provider is normal. Posting it publicly is not a good idea: combined with other information it identifies a specific line.
Quick answers
Is the ICCID the same as the EID?
No. The ICCID belongs to the SIM profile, the EID belongs to the eSIM chip in the phone. Install a new eSIM and you get a new ICCID, while the EID stays the same.
How many digits is an ICCID?
Usually 19 or 20. It always starts with 89, and the final digit is a check digit calculated from the ones before it.
Does the ICCID change when I top up?
No. A top up adds data to the profile you already have, so the ICCID stays the same. Buying a separate new eSIM gives you a new one.
Can someone use my ICCID to take over my line?
Not on its own. It identifies the SIM to the network, it is not a password, and your provider will ask for proof of account ownership before changing anything.