What is an SM-DP+ address, and what is the activation code?

A server and a ticket

The names come from SGP.22, the GSMA specification that governs how consumer eSIMs are downloaded. SM-DP+ stands for Subscription Manager Data Preparation, and the plus marks the enhanced version of an older server role used for machine SIMs. It is the system that prepares eSIM profiles and delivers them to phones. Its address is a domain name, just like a website's; the specification's own example is SMDP.GSMA.COM.

The matching ID is the ticket. The specification describes it as a unique identifier that links a download order created by the operator with the download request that arrives from a phone, and it requires the server to process only requests that contain a matching ID it knows.

The part of your phone that reads the code and talks to the server is called the Local Profile Assistant, or LPA. That is where the three letters at the start of every eSIM QR code come from.

Reading the code piece by piece

• LPA: only appears when the code is inside a QR image. It tells the phone this is an eSIM code.
• 1 is the format number. The specification sets it to 1.
• $ separates the fields.
• SMDP.GSMA.COM, in the example, is the SM-DP+ address.
• 04386-AGYFT-A74Y8-3F815, in the example, is the matching ID.
• Optionally, more fields after another $: a long number with dots, which identifies the server, and a final 1 if a confirmation code is required.

Put together, the specification's example inside a QR reads LPA:1$SMDP.GSMA.COM$04386-AGYFT-A74Y8-3F815. It also says that when the code is entered by hand, it is used as defined without the LPA: prefix, which is only there for QR codes. The whole thing can be up to 255 characters long. What the confirmation flag means in practice is explained in why your eSIM asks for a confirmation code.

Why one extra space breaks it

The specification is strict about the matching ID: it may contain only the digits 0 to 9, the capital letters A to Z and the hyphen. A space is not one of them. Nor is a full stop picked up at the end of a sentence, or a line break that slipped in when you copied from an email.

Because the server only accepts matching IDs it knows, any change produces a different ID that matches nothing. Swapping the letter O for a zero, dropping a hyphen or adding a space at the end has the same effect as typing a random code. The phone then reports that the code is invalid, even though the one you were given is fine.

The SM-DP+ address is just as unforgiving in a different way. It is a domain name, so a typo or a space means the phone cannot find the server at all. Copy and paste both values instead of retyping them, and check the first and last character after pasting.

Where you type it on iPhone and Android

On iPhone, Apple's route is Settings, Cellular or Mobile Data, Add Cellular Plan or Add eSIM, then Enter Details Manually at the bottom of the screen. The form asks for the SM-DP+ address and the activation code in separate boxes. If the phone then asks for a confirmation code, Apple says to enter the number your carrier provided.

On a Samsung Galaxy, Samsung's path goes through Settings, Connections, SIM manager, Add eSIM, the option to scan a QR code from your service provider, and then Enter activation code, where the code goes in a single field. On a Google Pixel, Google's route to add an eSIM is Settings, Network and internet, SIMs, Add SIM, Set up an eSIM. Menu names vary by model and software version.

The full method for installing without a camera, including the iPhone shortcut that reads a QR code from an email, is in how to install an eSIM without scanning the QR code.

Splitting the code into two boxes

If your provider sent only the long string and your phone asks for two values, split it at the dollar signs. The SM-DP+ address is everything between the first and the second $. The activation code is everything after the second $, up to the next $ if there is one.

Leave out LPA:1$ at the start; it belongs to neither box. Leave out anything after a third $ as well: a number with dots is the server's identifier, and a lone 1 at the end only tells the phone to ask for a confirmation code.

If your phone has a single box instead, enter the code as your provider wrote it. When a provider sends both versions, the QR and the text, they lead to the same profile, so use whichever is easier, but only once: the profile installs on the first phone that downloads it.

When everything is typed right and it still fails

Check the connection first. The phone uses these details to contact the server and download the profile there and then, so it needs Wi-Fi or another working connection.

Then check whether the eSIM is already on the phone. If an earlier attempt worked, a new line appears in the SIM or mobile data settings, and a second attempt with the same code will be refused. Our guide to the code is no longer valid explains what that message means.

If neither applies, write to the seller with a screenshot of the error. With Snoozim, the QR code and its details arrive by email, and the eSIM stays on the phone where it is installed, so it is worth asking before trying the same code many times. Check first that the phone supports eSIM and is unlocked.