Partially Addressed Mail: A Complete Guide

What is partially addressed mail?

Royal Mail describes Partially Addressed Advertising Mail as a standard addressed advertising product that 'identifies customers using sophisticated targeting options without the use of personalised data'. Every item carries a real, deliverable address, so it arrives with the rest of the household's post. The top line of the address is not a person's name. It is a generic or descriptive title that you choose.

That makes it an acquisition tool. You can mail households that look like your best customers without renting or buying a named mailing list. For how it compares with fully addressed mail and unaddressed door drops on attention, response and cost, see addressed vs partially addressed vs door drops.

How targeting works

Royal Mail's user guide sets out two ways to choose postcodes, and recommends combining them.

1. 1

   Topping up

   Map your existing customers by postcode. Where a postcode already has a high proportion of customers, mail the remaining households, on the assumption that their neighbours are good prospects.

2. 2

   Look-alikes

   Profile your best customers with a geo-demographic tool such as MOSAIC or CAMEO, then select postcodes elsewhere with similar characteristics. This finds new areas where people are likely to want what you sell.

3. 3

   Combine both

   Top up in your strongest postcodes and add look-alike postcodes to widen reach. Royal Mail Marketreach suggests that, for the same budget, one partially addressed mailing can reach around 30% more households than a fully addressed mailing, although it notes this varies by business.

Data and suppression rules

To qualify for partially addressed prices, Royal Mail requires every household in each targeted postcode to be mailed, except those you are required to remove. The user guide lists the rules:

• Remove households where an existing customer lives.
• Remove households where someone has opted out of receiving this kind of mail.
• Remove postcodes that contain only one household.
• Remove addresses that themselves contain personal data. Some PAF records use a surname to identify a property, such as 'Roberts Household'. Royal Mail says these appear in brackets in address line 1.
• Keep a documented procedure for suppressing customer and prospect data, and run every mailing against your suppression files 30 days or less before the items are delivered.
• Keep each suppression file for at least two years.
• Optionally, suppress against the Mailing Preference Service (MPS) at household level.
• Do not include any personally identifiable information on the item, and do not address it to a named person.

This is standard data work for a mailing house. Our data processing team already runs PAF validation, de-duplication, gone-away and MPS suppression for addressed campaigns.

Formats, specifications and the declaration

Apart from single-sheet postcards, all partially addressed mail must be posted with Mailmark, Royal Mail's barcode for sorted mail. Folded and glued single-sheet mailers must follow Royal Mail's single-sheet guidelines, and Mailmark postcards have a detailed specification. Royal Mail lists a size of 140mm × 90mm to 240mm × 165mm, 120–150gsm matt or silk paper, and a specific fold and glue construction.

You must also send Royal Mail a sample of each mailing at the time of posting, either as a seed item in the mailing or as a PDF, so its content control team can check that it meets the specification.

How we can help

Print, data and Mailmark sortation under one roof

We print, enclose and sort to Mailmark in Keighley as a Royal Mail Mailmark accredited supplier, ready for Low Sort posting.

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How much does partially addressed mail cost?

For comparison, an Economy Low Sort Mailmark Advertising Mail letter costs 30.4p to 29.0p over the same period. Mailings of fewer than 10,000 partially addressed letters may be charged at the Standard Unsorted price, which is 74.0p for 2nd Class, so the 10,000 minimum matters. Postage is only part of the cost. Add print, enclosing and data work, and see how much direct mail costs in the UK for the full picture.

What results can you expect?

Response is lower than for mail sent to your own customers, as you would expect for acquisition, but the cost per item is lower too. Royal Mail Marketreach case studies show what well-targeted campaigns can do. Subway reported a 5.4% redemption rate, and Wiltshire Air Ambulance a 2% response with a £19 average donation. For wider benchmarks see direct mail response rates and ROI.

Making partially addressed mail work

• Use a relevant title. 'Pizza Lover' or 'Pet Owner' gets more attention than 'The Occupant'. Royal Mail Marketreach recommends a title that reflects the audience you are targeting.
• Write for the household, not the person. You do not know who will open it, so avoid copy that implies you do.
• Lead with a clear offer. This is a first introduction. Give one strong reason to respond and one easy way to do it, such as a QR code, a short URL or a voucher code.
• Track every response. Use a unique code or landing page per mailing, or per postcode group, so you can see which areas respond and refine the next selection.
• Keep the format simple. Single-sheet mailers and letters keep print and postage costs down. See letter vs postcard vs self-mailer for help choosing.
• Plan suppression early. Allow time to get your customer file and opt-outs ready, and remember the 30-day rule.

Partially addressed mail sits alongside other forms of mail. Many advertisers mail customers by name and use partially addressed mail or door drops to reach new households in the same campaign. Our guide to planning a direct mail campaign covers the full process, and you can find more advice in our guides library.