New UK rules on scam texts: the SIM farm ban (29 October 2026) and Ofcom's 2027 blocking rules

The timeline

SIM farms: what becomes a crime on 29 October 2026

A SIM farm is a device that can use five or more physical SIM cards at the same time or in turn, to make calls or send texts to phone numbers. The Home Office says scam texts are frequently traced back to them, and Ofcom says scammers typically use them to send texts person to person.

The Crime and Policing Act 2026 received Royal Assent on 29 April 2026. Its section 151 makes possessing a SIM farm an offence, and section 152 does the same for supplying one to another person. A supplier charged under section 152 has a defence if they can prove the supply was made in the course of their business or that they had a good reason or lawful authority for having the SIM farm, and that they took reasonable steps to check the buyer would have a good reason and kept a record of the supply. Regulation 5 of the commencement regulations (SI 2026/960) brings sections 151 to 153 into force on 29 October 2026; the Home Office guidance gives the same date and says a conviction can bring a fine.

For possession, a good reason or lawful authority is a defence, and the Act names examples: broadcasting, running public transport, running an electronic communications network and tracking freight. The Home Office says a six-month transition period applies before the offences take effect.

Person-to-person texts: from 18 January 2027

Person-to-person texts come from ordinary mobile numbers, such as the "Hi Mum" scam. Ofcom's new conditions require mobile networks to:

• set volume limits for pay-as-you-go SIMs, to make it harder for scammers to text large numbers of people;
• stop numbers identified as responsible for scams from sending messages, with a way to receive scam reports from customers and from anti-fraud organisations;
• block scam texts in transit by detecting scam web links and phone numbers, based on those reports.

Business texts: from 15 July 2027

Business texts (Ofcom calls them A2P, application-to-person) are sent by organisations through messaging services, and often show a name, such as a bank or “HMRC”, instead of a number. Ofcom says scammers who get into business messaging can send texts under a named organisation, and can even spoof a name so their text lands in an existing conversation. From 15 July 2027, networks and the aggregators that pass business texts on must:

• run Know Your Customer checks on a business before it can send;
• prevent fake sender names, by checking each name against those checks;
• keep checking traffic and investigate fraud reports promptly, and block senders when scam activity is found.

One duty sits with the mobile networks that deliver texts to their customers (Ofcom calls them terminating mobile operators) alone: they must keep policies on protected sender names (those of organisations often copied by scammers, such as banks and delivery firms) and generic ones such as “Customer service”. Ofcom says the other providers must check any new sender name against those policies.

What the rules don't cover

For scam messages in iMessage, RCS chats and WhatsApp, use the app's own report button: see scam texts from an email address, iMessage or RCS.

What you'll notice

Most of the change happens inside the networks: Ofcom's aim is that fewer scam texts reach you at all. Two details matter if something goes wrong:

• If a number or a message of yours is blocked by mistake, the new rules give mobile users a right to challenge the decision, and providers must look for and fix messages blocked in error.
• Ofcom considered making providers tell senders when a message is blocked, and decided not to.

Why your 7726 reports matter more

The new blocking duties run on reports: networks must block numbers and links “based on scam reports from customers and third parties”. Forwarding a scam text to 7726 is how you send one. How to forward a text to 7726, and how many texts are reported and blocked today.

Until the rules start

Ofcom's rules don't start until January 2027, and the checks on business sender names not until July 2027. Until then: treat any text that asks you to tap a link or give details with suspicion, even under a familiar name such as HMRC or a delivery firm; turn on your phone's spam filters (how to block spam texts); and paste anything doubtful into the scam text checker.

Sources

• Ofcom statement, the new rules in brief: Ofcom, 'Combatting mobile messaging scams: New rules and guidance', statement published 15 July 2026 (checked on 2 October 2026 against the Internet Archive copy of 29 September 2026, as the live site blocks automated access; footnote numbers left out), overview, 'What we have decided - in brief': "Setting volume limits for pay-as-you-go (PAYG) SIMs, to make it harder for scammers to message large numbers of potential victims. ... Blocking numbers used by scammers: preventing scammers from sending messages from numbers that have been identified as responsible for scams. ... Blocking scam messages in transit: identifying and blocking scam messages in transit on their networks by detecting scam URLs and telephone numbers, based on scam reports from customers and third parties. ... Conducting due diligence: preventing criminals from using A2P services to contact potential victims by ensuring that effective Know Your Customer (KYC) checks are made at the onboarding stage. ... Preventing the use of fake alphanumeric sender IDs, including by corroborating Sender IDs against information gathered through KYC checks and maintaining a policy on restricting the use of protected sender IDs and generic sender IDs. ... a right for mobile users to challenge a decision to block a number or message ... We also consulted on a requirement for providers to notify message senders when certain messages are blocked. In the light of new evidence, we have decided not to implement this proposal. ... The new rules and new guidance that apply to P2P messaging will come into effect on 18 January 2027. Those that apply to A2P messaging will come into effect on 15 July 2027." Ofcom copyright. — https://www.ofcom.org.uk/siteassets/resources/documents/consultations/category-3-4-weeks/consultation-combatting-mobile-messaging-scams/main-document/statement-combatting-mobile-messaging-scams.pdf?v=423155, read on 2026-10-02
• Ofcom statement, what the rules cover (para 2.31 to 2.35, 1.9): Ofcom, 'Combatting mobile messaging scams: New rules and guidance', statement published 15 July 2026 (checked on 2 October 2026 against the Internet Archive copy of 29 September 2026, as the live site blocks automated access; footnote numbers left out), overview, paragraphs 1.9 and 2.31 to 2.35: "Setting volume limits for pay-as-you-go (PAYG) SIMs, to make it harder for scammers to message large numbers of potential victims. ... Preventing the use of fake alphanumeric sender IDs, including by corroborating Sender IDs against information gathered through KYC checks ... The new rules and new guidance that apply to P2P messaging will come into effect on 18 January 2027. Those that apply to A2P messaging will come into effect on 15 July 2027. ... The measures do not apply to services that Ofcom regulates under the Online Safety Act, such as online messaging apps. ... Widely adopted online messaging apps such as WhatsApp and proprietary online messaging standards such as iMessage use functionality that is not dependent on telephone numbers and they are not regulated under the Communications Act. ... Messages from these false base stations can bypass network-level protections and tackling them requires a coordinated response from regulators and law enforcement." Ofcom copyright. — https://www.ofcom.org.uk/siteassets/resources/documents/consultations/category-3-4-weeks/consultation-combatting-mobile-messaging-scams/main-document/statement-combatting-mobile-messaging-scams.pdf?v=423155, read on 2026-10-02
• Ofcom statement, SMS and RCS (para 2.34 to 2.36): Ofcom, 'Combatting mobile messaging scams: New rules and guidance', statement published 15 July 2026 (checked on 2 October 2026 against the Internet Archive copy of 29 September 2026, as the live site blocks automated access; footnote numbers left out), paragraphs 2.34 to 2.36: "SMS and MMS are regulated under the Communications Act, but the messaging services landscape is changing continually. ... Services such as RCS share characteristics of the traditional messaging services like SMS and MMS but also share characteristics of online messaging apps. Whether such a service is now, or could in the future be, regulated under the Communications Act will depend on how it is implemented in the UK. It is for operators to determine in the first instance whether their current implementation of RCS constitutes a service that is regulated under the Communications Act" Ofcom copyright. — https://www.ofcom.org.uk/siteassets/resources/documents/consultations/category-3-4-weeks/consultation-combatting-mobile-messaging-scams/main-document/statement-combatting-mobile-messaging-scams.pdf?v=423155, read on 2026-10-02
• Ofcom statement, how scam texts are sent (para 2.23, 2.26): Ofcom, 'Combatting mobile messaging scams: New rules and guidance', statement published 15 July 2026 (checked on 2 October 2026 against the Internet Archive copy of 29 September 2026, as the live site blocks automated access; footnote numbers left out), paragraphs 2.23 and 2.26 and footnote 41: "To send P2P messages, scammers typically use illegal SIM farm devices. These devices allow scammers to generate messages and transmit them over mobile networks using SIMs. Scammers insert SIMs into SIM farms, which typically house tens or hundreds of SIMs. ... With access to A2P messaging services, scammers may be able to send messages with an alphanumeric sender ID, so that their messages appear to the recipients to come from a named organisation (such as ‘HMRC’). This can make messages appear more credible to recipients. ... The alphanumeric ID may look convincing, or scammers may spoof an ID and send new messages to an existing message thread so that the messages appear to come from a legitimate sender." Ofcom copyright. — https://www.ofcom.org.uk/siteassets/resources/documents/consultations/category-3-4-weeks/consultation-combatting-mobile-messaging-scams/main-document/statement-combatting-mobile-messaging-scams.pdf?v=423155, read on 2026-10-02
• SI 2026/960, SIM farm offences start: The Crime and Policing Act 2026 (Commencement No. 3 and Saving Provisions) Regulations 2026 (SI 2026/960, made 2 September 2026), regulation 5, legislation.gov.uk (Crown copyright): "The following provisions of the 2026 Act come into force on 29th October 2026— ... sections 151 to 153 (SIM farms);" Contains public sector information licensed under the Open Government Licence v3.0. — https://www.legislation.gov.uk/uksi/2026/960/made, read on 2026-10-02
• Crime and Policing Act 2026, section 151: Crime and Policing Act 2026, section 151 'Possession of a SIM farm', legislation.gov.uk (Crown copyright): "A person who possesses a SIM farm commits an offence. ... It is a defence for a person charged with an offence under this section to prove that the person had a good reason or lawful authority for possessing the SIM farm." Contains public sector information licensed under the Open Government Licence v3.0. — https://www.legislation.gov.uk/ukpga/2026/20/section/151, read on 2026-10-02
• Crime and Policing Act 2026, section 152: Crime and Policing Act 2026, section 152 'Supply of a SIM farm', legislation.gov.uk (Crown copyright): "A person who supplies a SIM farm to another person commits an offence. ... It is a defence for a person charged with an offence under this section (“the supplier”) to prove— (a) that— (i) the supply was made in the course of a business carried on by the supplier, or (ii) the supplier had a good reason or lawful authority for possessing the SIM farm (before the supply was made), (b) that, before the supply was made, the supplier took reasonable steps to satisfy themselves that the person to whom the SIM farm was to be supplied would have a good reason or lawful authority for possessing it, and (c) that, before the supply was made, the supplier made a record of the specified information relating to the supply." Contains public sector information licensed under the Open Government Licence v3.0. — https://www.legislation.gov.uk/ukpga/2026/20/section/152, read on 2026-10-02
• Ofcom statement, sender-name policies (para 6.51 to 6.52): Ofcom, 'Combatting mobile messaging scams: New rules and guidance', statement published 15 July 2026 (checked on 2 October 2026 against the Internet Archive copy of 29 September 2026, as the live site blocks automated access; footnote numbers left out), paragraphs 6.51 and 6.52: "To further protect against the abuse of alphanumeric sender IDs, GC C9.13 requires terminating mobile operators to implement and maintain appropriate and effective policies, systems and processes on the use of specific protected IDs, generic IDs and special alphanumeric characters within alphanumeric IDs. We have imposed this requirement on terminating mobile operators only, as these providers should have the ability to communicate sender ID restrictions to their downstream supply chain and enforce them with respect to all traffic that downstream providers transfer to them. ... All other providers will, where applicable, need to review any proposed use of new alphanumeric sender IDs against these policies (GC C9.11(b))." Ofcom copyright. — https://www.ofcom.org.uk/siteassets/resources/documents/consultations/category-3-4-weeks/consultation-combatting-mobile-messaging-scams/main-document/statement-combatting-mobile-messaging-scams.pdf?v=423155, read on 2026-10-02
• Home Office, SIM farm guidance (July 2026): Home Office (GOV.UK), 'Crime and Policing Act 2026 Guidance: Offences relating to the possession and supply of SIM farms and legitimate uses of multiple SIM devices' (published 27 July 2026): "SIM farms are devices that are capable of using five or more physical SIM cards simultaneously or interchangeably ... In practice, SIM farms are commonly used by criminals to carry out fraud, including scam calls and scam text messages. ... Scam texts are frequently traced back to SIM farms, electronic devices which can hold sometimes hundreds of physical SIM cards that can then be used to send out thousands of scam texts and calls in seconds. ... It is an offence to possess a SIM farm without a good reason or lawful authority. ... It is also an offence to supply a SIM farm unless certain conditions are met. ... The Act received Royal Assent on 29 April 2026. A six-month transition period will apply before the offences come into effect. ... From 29 October 2026, a person convicted of an offence may be liable, on summary conviction, to a financial penalty." Contains public sector information licensed under the Open Government Licence v3.0. — https://www.gov.uk/government/publications/possession-and-supply-of-sim-farms/crime-and-policing-act-2026-guidance-offences-relating-to-the-possession-and-supply-of-sim-farms-and-legitimate-uses-of-multiple-sim-devices-accessi, read on 2026-10-02
• NCSC, forwarding to 7726: NCSC, Report a scam text: "Most phone providers are part of a scheme that allows customers to report suspicious text messages for free by forwarding it to 7726. If you forward a text to 7726, your provider can investigate the origin of the text and arrange to block or ban the sender, if it's found to be malicious." — https://www.ncsc.gov.uk/collection/phishing-scams/report-scam-text-message, read on 2026-09-29

Quotes from GOV.UK, legislation.gov.uk, mygov.scot, the NCSC, the ICO and NHS England are used under the Open Government Licence v3.0; material from Ofcom is Ofcom copyright. Other pages are summarised in our own words or quoted briefly, with a link. How we check.