What is EID number
You can see the EID number on the phones. If you are wondering what an EID number is, I will now tell you about it. EID is “Embedded Identification Document”. The SIM card ID is built into the phone. It is a new format of Sim-card, which allows you to use services of mobile operators without the need to use an external Sim-card. Such built-in Sim-cards are called eSIM.
I should note that eSIM cards appeared not so long ago, In the iPhone EID appeared since 2018, in some models of the iPhone 8 and XS. The presence of EID allows the iPhone to use two phone numbers, and different operators.
EID for Embedded SIM (eSIM) explained

History of EID and electronic sim cards. In 2014, the concept of a new generation of sim cards was adopted. This concept implied a complete rejection of the use of removable sim cards. The sim card chip is built into the phone or other device at the factory. Built-in sim-card (eSIM) has a unique number, this number is called eID and consists of 32 digits. eSIM-card is not tied to the operator, using EID, you can connect your phone to any operator that supports work with built-in sim-cards. This concept has become popular, the iPhone14 from 2022 will be available without a SIM card slot at all.
Why do I need an EID number
The EID is needed to connect to the mobile operator’s services. If your mobile operator supports working with eSIM cards, and nowadays almost all operators support getting a number and tying a phone number to your smartphone without a sim card, you can use mobile network services without having to buy a sim card. In addition, depending on the type of device, you can connect multiple phone numbers, up to 5 numbers, but only one or two will be active, depending on how many radio modules are in the phone connected to the eSIM.
How to find an EID number
The EID number is in the phone’s memory and is also written on the packaging box of the electronic device. You may need this number when you use the phone, but it is unlikely, installing the number on the eSIM is automated, you only need to get a QR code from the mobile operator and then scan it with your phone. Linking your EID to the number will be done automatically by the phone and the operator.
32 digit EID number

There is no point in describing the structure of the 32-character EID number, the average user simply does not need it. But it is a unique number in which there is information about which organization has registered this number and the number itself, it should eliminate the duplication of this number.
How to activate eSIM using EID
The procedure for activating the built-in SIM card depends on the mobile network operator. But it usually looks like this.
The operator has to get your EID number and link it to your account, and assign your EID to your cell phone number. All this happens automatically when your phone receives a QR-code, generated by the operator (the QR-code will be provided to you by the mobile operator), how this happens is individual for each operator, with some the code will be sent to your e-mail, with others you’ll need to scan the code in your personal account at the website of the operator. But in any case, everything starts with registering with a mobile operator and getting the code.
EID connection on postpaid tariffs, contract
You need to get a QR code, this QR code is generated by the mobile operator. You contact a representative of the mobile operator in one of the stores. An account will be created for you, or if you already have an account, they will simply transfer your existing phone number. Why you should visit the store, generally phone numbers tied to an authorized account are more secure, the carrier checks your records without you visiting the store in person and does not make any changes or adjustments to your account. Such phone numbers are tied to bank cards and other services that require maximum security against unauthorized access. Although it depends on the country, many countries already use digital signatures or customer identification through other organizations that can verify your identity, such as a bank.
Connection of telephone number using EID at prepaid tariffs
Since phone numbers with prepaid rates are less secure, to activate the built-in SIM card, just download the operator’s mobile application and select a tariff plan. If you transfer the phone number from an ordinary Sim card to eSim, you may also need to visit the store.
Hey, where did you get the term “Embedded Identification Document” from? Will you please either cite your sources or specify which standard you are pulling this terminology from? The GSM Association standard SGP.29 v1.0 EID Definition and Assignment Process defines EID as the “eUICC Identifier”. You seem to have pulled this from a non-authoritative source or your imagination, judging by the Google search results for this term. Google only returns your article, a misinformed splaitor.com article, some random French Yahoo blog post, and my Wikipedia article stub that mistakenly used your incorrect terminology. Please stop polluting the Internet.
Dear Stephen Charles Thompson, You can contact Google Support (Pixel phone). I will quote an excerpt from the document (The phone needs an IMEI (International Mobile Equipment Identity Number) number to use the mobile network. The phone also needs an EID (Embedded Identity Document) number to use eSIM. When you install a new SIM card, you may need to tell the operator the IMEI 1, IMEI 2 or EID number of your phone). https://support.google.com/pixelphone
I think Google, the maker of the Pixel phone, is a pretty authoritative source.
You should understand that ID is a generic name, for example, your driver’s license is an ID, your insurance card is an ID, and your building access card is also an ID. EID is also a generic name for a document that electronically verifies something.