What is the Mailing Preference Service and who runs it?
The Mailing Preference Service (MPS) is the UK's opt-out register for addressed consumer direct mail. It was established in 1983 and is administered by the Data & Marketing Association (DMA). UK residents can register at no cost by submitting their name and address via mpsonline.org.uk; once processed, their record appears on the register and should not receive unsolicited direct mail from any organisation that has performed an MPS wash.
As of the mid-2020s, the MPS register holds several million registrations. The count grows every month as new consumers sign up, which is one of the principal reasons why a stale MPS suppression file is a compliance liability rather than just a minor housekeeping oversight.
The DMA publishes guidance on how to access MPS data. Organisations that are DMA members can query the register directly as part of their membership. Non-members typically access MPS through a licensed data cleansing bureau or data supplier who holds a current DMA licence to process and supply suppressions. Your data provider should be able to confirm whether they apply MPS as a standard step at point of supply, or whether you need to arrange a separate wash.
Is the MPS wash a legal requirement?
This question trips up a surprising number of direct mail teams. The short answer: MPS compliance is not a statutory requirement in the way that TPS suppression is for telephone marketing. The Privacy and Electronic Communications Regulations (PECR) govern electronic communications, specifically telephone, fax, email, and SMS. Postal mail falls outside PECR's scope entirely.
That said, ignoring MPS is not a safe option. The Information Commissioner's Office (ICO) takes the position that processing personal data to send mail to someone who has clearly registered an objection raises fairness concerns under UK GDPR Article 5(1)(a). A data subject who receives a mailing after registering on MPS has grounds to raise a complaint, and repeated complaints to the ICO about the same organisation can attract an investigation. The DMA Code of Practice, meanwhile, makes MPS compliance a binding obligation for DMA members, with sanctions for persistent breach.
In practice, the compliance argument is secondary to the commercial one. Mailing someone who has explicitly asked not to receive direct mail wastes postage, suppresses response, and poisons brand perception. Those 5 to 10 percent of records you remove at MPS are not prospects; they are people who will bin the piece on sight at best, or complain at worst.
MPS versus TPS: a common confusion
Some marketers conflate MPS with TPS. They are separate registers for separate channels. TPS (Telephone Preference Service) is statutory under PECR and covers unsolicited live calls to consumers. MPS is an industry-run register covering addressed postal mail. A consumer registered on TPS but not MPS can legally receive direct mail. One registered on MPS but not TPS can legally receive a sales call, though that would be commercially questionable. Most fully opted-out consumers register on both.
How does the MPS wash process work?
The mechanics are straightforward. Your consumer postal file is submitted (securely, under a data processing agreement) to the MPS bureau or your data provider's cleansing infrastructure. The submitted records are matched against the current MPS register by name and postcode or full address. Any record that matches a MPS registrant is flagged for suppression, meaning it is removed from the mail-ready output file before print and despatch.
Matching logic matters here. MPS is a name-and-address register, not just a postcode register. A match requires the individual's name (or a recognisable variant) at a matching address. This means:
- A mailing addressed only to "The Householder" at a postcode is not subject to MPS, because there is no named individual to match against the register.
- If a person moves house, their MPS registration stays linked to the address where they registered. They are not automatically suppressed at the new address, which is one reason NCOA (National Change of Address) should run first.
- Name variants and maiden names can cause matching gaps. No MPS process achieves 100 percent suppression; professional bureaux use fuzzy-match logic to minimise misses, but the odd registration will slip through.
After the wash, your bureau should provide a suppression report: total records in, MPS matches found, records passed for mailing. Retain this report as evidence of compliance, particularly if you are using the ICO's legitimate interests basis for the broader campaign.
Postal suppression workflow: the right order
MPS does not operate in isolation. A complete consumer postal suppression workflow typically includes three or four steps, and the sequence is important. Running them in the wrong order wastes processing costs and introduces errors.
| Step | Suppression type | What it removes | Why this order |
|---|---|---|---|
| 1 | NCOA (National Change of Address) | Gone-away records; updates address for movers | Current addresses must be in place before MPS matching; also removes undeliverable records before paying for further suppression steps |
| 2 | Deceased suppression | Records where the named individual has died | No point paying for MPS processing on records that will never convert; also reduces distress mail risk |
| 3 | MPS wash | Consumers registered as not wishing to receive unsolicited direct mail | Operates on a clean, current file; MPS matching on stale addresses wastes licence fees and misses moved registrants |
| 4 | Client suppression file | Recent complainants, existing customers (if excluded), prior opt-outs from your own database | Applied last as the most bespoke layer; prevents mailing people you already know should not receive this piece |
In our experience, organisations that skip NCOA before MPS find their removal rates slightly inflated because the MPS register contains old addresses that no longer correspond to the individual. Running NCOA first gives you a cleaner match and a more accurate picture of genuine opt-outs on your current file.
How often should you run the MPS wash?
The MPS register grows every day. The DMA does not publish a real-time registration count, but industry estimates suggest tens of thousands of new registrations occur each month. A suppression file that was current in January has missed all of those by April.
The practical rule is simple: wash before every send. For a business running four direct mail campaigns per year, that means four separate MPS washes. For a business running a rolling programme (say, a monthly customer-acquisition pack), a new wash before each despatch is the gold standard, though a quarterly refresh of the suppression file is a widely accepted minimum where operational constraints prevent per-campaign processing.
What you should not do is wash once, build a standing suppression file, and run it unchanged for twelve months. A year-old MPS file is likely to contain a meaningful number of consumers who have since registered, and any one of them mailing a complaint to the ICO constitutes evidence that your suppression process is inadequate.
Cost considerations
MPS processing is not free, but it is not expensive relative to print and postage. Bureau fees vary, but expect costs in the region of £30 to £80 per thousand records processed, depending on volume, the bureau's pricing model, and whether the MPS wash is bundled with NCOA and deceased suppression as a single postal cleansing service. On a 10,000-record mailing at a typical postage cost of 35p to 65p per piece, the suppression processing cost is a small fraction of the total campaign spend. The return on investment from not mailing 500 to 1,000 opted-out records is immediate.
How does MPS fit with NCOA and the wider postal cleansing picture?
MPS and NCOA postal cleansing are complementary but distinct processes. NCOA updates or removes records based on address accuracy and deliverability; it has no bearing on whether the individual wants to receive mail. MPS removes records based on the individual's stated preference; it has no bearing on whether the address is deliverable.
A consumer who has moved house and also registered on MPS needs both: NCOA finds their new address, then MPS suppresses them anyway. A consumer who has moved but not registered on MPS still needs NCOA to update the address for the mailing to reach them. Running one without the other leaves gaps in both deliverability and compliance.
For a detailed breakdown of how postal list selection sits upstream of both, see our guide on direct mail list selection in the UK.
Does PECR apply to postal direct mail?
No. The Privacy and Electronic Communications Regulations 2003 (PECR) apply to electronic direct marketing: telephone calls, faxes, emails, and SMS. Postal mail is not an electronic communication and is not regulated by PECR. This is the statutory distinction that separates MPS from TPS: TPS is backed by PECR's enforcement mechanism, which allows the ICO to levy fines for unsolicited calls to registered numbers. No equivalent statutory penalty exists for mailing an MPS-registered address.
That said, UK GDPR's fairness principle (Article 5(1)(a)) and the right to object under Article 21 provide a regulatory basis for the ICO to scrutinise postal marketing practices. The ICO has made clear in published guidance that it expects direct mail campaigns to respect well-known opt-out registers, of which MPS is the primary one for postal marketing in the UK.
MPS for bought data versus house data
The MPS wash question arises in two distinct contexts, and the answer is the same in both cases: wash before you mail.
For bought consumer data, the data supplier may have already applied an MPS suppression at the point of extraction from their file. A responsible supplier will confirm this in writing, including the date the MPS wash was run. If the wash was performed more than three months before you mail, or if the supplier cannot confirm when it was done, run a fresh wash. You are the data controller at the point of mailing; the supplier's earlier suppression does not absolve you of responsibility.
For house data (your own customer or prospect database), MPS applies whenever you are running an unsolicited marketing communication to someone who is not already an active customer. Active customers receiving service communications or legitimate marketing under an existing relationship have some limited additional exemptions, but these are narrow; if in doubt, include them in the MPS wash.
SortedIQ's fully opt-in consumer file under UK GDPR and PECR consent is supplied with MPS suppression applied at extraction. Buyers are advised to confirm the suppression date with us at point of order and, for campaigns running more than three months after the extraction date, to arrange a refresh wash before despatch.