Rules and compliance2 min read
TPS and CTPS, explained properly
If you make outbound calls to find customers, these registers decide who you may legally ring. The trap is that business numbers are not automatically fair game.
Published 17 June 2026 · Updated 15 August 2026
The Telephone Preference Service and its corporate equivalent are opt out registers. Numbers on them must not receive unsolicited marketing calls, and the obligation to check sits with the caller.
This is general information rather than legal advice. If you run outbound campaigns at scale, take proper advice.
What each register covers
TPS covers individual subscribers, which means residential numbers and, importantly, sole traders and most partnerships. CTPS covers corporate subscribers, meaning limited companies, LLPs and public bodies.
Both are backed by the Privacy and Electronic Communications Regulations, and enforcement sits with the Information Commissioner's Office.
The sole trader trap
This is where most well intentioned callers go wrong. A number that looks like a business line, advertised on a van and listed on a website, may still be registered with TPS if the business is a sole trader or partnership.
So screening a business list against CTPS alone is not enough. Any list of small local businesses will contain a substantial number of sole traders, and calling them is the same breach as calling a household.
Easier to hear than to read about
Callwise answers your phone the way this article describes. Ring it, ask it something awkward, and see whether it holds up.
Talk to our AI assistantWhat counts as a marketing call
Promoting your goods or services. Service calls to existing customers about something they have bought are different, as are calls somebody has specifically asked you to make.
The boundary is not always obvious. A call that begins as service and turns into a pitch is a marketing call in substance, and that is how it will be judged.
Practical compliance
Screen before you dial, keep a record that you screened, and honour any request not to be called immediately and permanently. Keep your own do not call list, because a request made to you binds you regardless of the registers.
- Screen every list against both TPS and CTPS before calling
- Rescreen regularly, because registrations change
- Keep evidence of when each number was screened
- Maintain your own suppression list and honour it forever
- Identify yourself and give a contact address on request
Inbound calls are not affected
None of this applies to answering somebody who rang you. The registers restrict unsolicited outbound marketing, not your ability to pick up your own phone.
That distinction matters if you are considering an AI receptionist. Answering inbound calls raises data protection questions, not PECR ones.
Questions people ask
How long after registration must we stop calling?
TPS registrations take effect after a short period, but the safe practice is to rescreen frequently and treat a fresh registration as immediately binding.
What are the penalties?
The ICO can issue substantial fines for breaches, and it publishes enforcement action, which carries its own cost.
Read next
Is it legal to use an AI receptionist?
Answering your own inbound calls with software is lawful. The rules that matter are about data and transparency, not about automation itself.
Recording calls under UK GDPR
Recording business calls is lawful and routine. Doing it without telling anyone, or keeping the recordings forever, is where businesses get into difficulty.
Security questions worth asking
You are about to send every conversation with every customer through somebody else's system. It is worth ten minutes of questions.
Hear it answer a call
Ring the assistant and ask it the awkward question your customers always ask. If you like what you hear, it will book you in there and then.
Talk to our AI assistantNo form, no sales call. Thirty seconds on the phone with the thing itself.