ESIM
electronically embedded SIM card, works as an already built-in chip in most of new phones
An eSIM (embedded subscriber identity module) is a form of SIM card that is embedded directly into a device as software installed onto an eUICC chip. In contrast to physical SIM cards, users can connect to and change mobile network operators via the device settings and without the need to physically add or swap a SIM card from the device. A single eSIM plan can connect to several mobile network operators. Devices can hold upwards of 20 eSIM plans simultaneously, with 1 or 2 active.
To reduce costs, many eSIM plans only provide data and do not include a phone number. Most phones and tablets released in 2018 or later support eSIM technology. If a phone is bought directly from a carrier with a SIM lock, the phone can only add eSIMs from the carrier that locked the phone, even after a carrier unlock.
Technical specifications
The eUICC chip used to host the eSIM is installed via surface-mount technology at the factory and uses the same electrical interface as a physical SIM as defined in ISO/IEC 7816 but with a small format of 6 mm × 5 mm. Once an eSIM carrier profile has been installed on an eUICC, it operates in the same way as a physical SIM, complete with a unique ICCID and network authentication key generated by the carrier. If the eSIM is eUICC-compatible, it can be re-programmed with new SIM information.
The public source identifies “ESIM” as electronically embedded SIM card, works as an already built-in chip in most of new phones. This brief keeps that definition visible, then builds a research path around ESIM, electronically and embedded.
Why this record matters
A short description can identify a subject without explaining its stakes. For “ESIM”, the useful work is to connect “electronically embedded SIM card, works as an already built-in chip in most of new phones” to the records capable of establishing context and consequence.
Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Sep 10, 2026. The linked authority identifier is Q56315412. None of the 0 selected statements returned an explicit reference. The first chronological checks are 2018.
A concise general-reference account can conceal disagreements about scope, terminology or the weight assigned to individual sources. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.
- Subject orientation
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The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “ESIM”, its source revision and the description used here.
- Expand the search: follow ESIM primary sources, ESIM archive and ESIM research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
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Search terms from this dossier
This entry incorporates text from “ESIM” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.