What does form OS1 ask for, and what comes back?
Form OS1 is a search, not a registration: it changes nothing on the register except to record the priority it confers. Almost every OS1 is now made electronically through the HM Land Registry portal, but the fields are the same as the paper form. The fields below follow the edition of form OS1 dated 28 February 2022, checked 20 September 2026. Check against the form in force when you search. HM Land Registry Practice Guide 12 (official searches and outline applications) explains each field, the priority rules and what happens when two searches collide.
What comes back is an official search certificate stating whether any adverse entry has been made since the search-from date, listing any that has, and giving the date on which the priority period expires.
| Field | What it asks for | Common mistakes |
|---|---|---|
| 1, Administrative area | The local authority district for the property | A former or neighbouring authority |
| 2, Title number | The registered title being acquired or charged, in whole | A title of which only part is passing, that is OS2 |
| 3, Registered proprietor | The full names of the current registered proprietors, as on the register | The seller's current name where the register still shows a former one |
| 4, Payment of fee | How the HM Land Registry search fee is paid | Unpaid fee, so the search is not processed and no priority starts |
| 5, Property | The address as shown in the property register | A marketing address that differs from the register |
| 6, Search from date | The date of the official copies being relied on | A guessed date; the date of the contract instead of the copies |
| 7, Applicant | The full name of the person who will be registered, buyer, lessee or lender, in whose favour priority is claimed | The seller, or the conveyancer, named as applicant |
| 8, Reason for search | Whether the applicant intends to purchase (P), take a lease (L) or take a charge (C) | The wrong letter, so the priority protects the wrong disposition |
| 9, Person making the search | Name, address, reference and contact details of the conveyancer or applicant | A reference that cannot be matched to the file when the result arrives |
| What comes back | Official search certificate: adverse entries since the search-from date, or none; and the priority expiry date | Reading "no adverse entries" as a clean title. The search shows only what changed after the copies |
Can I make an official search myself?
You can: form OS1 costs nothing to download and can be posted with the fee. There is no identity requirement for a search. But the search is only useful if you are about to register something, and if you are buying with a mortgage the lender will require a conveyancer to act, make the search in the right name and certify the result. A search made by a buyer acting alone that names the wrong applicant, or lapses before the AP1 is lodged, protects nothing.
An unrepresented buyer who does register a transfer will also face HM Land Registry's identity requirement, form ID1 (with ID5 where the check was by video), on the AP1 that follows the search (Practice Guide 67, updated 1 September 2026). The search is the easy part; the registration within priority is where it goes wrong.
| Doing it yourself | With Property Law Online | |
|---|---|---|
| Timing the search | Your judgement | Timed so priority covers registration with margin |
| Search-from date | You check the official copies | Checked against the copies on file |
| Applicant name | You choose | Matched to the transfer, lease and mortgage offer |
| Reading an adverse result | Your own research on what the entry means | Read and resolved before completion |
| Lodging within priority | You, with the land tax certificate and the AP1 | Diarised, lodged, confirmed to you in writing |
| Identity evidence on the AP1 | ID1 (with ID5 where the check was by video) | Dealt with through our own verification |
| Cost | HM Land Registry search fee; your time and risk | Included in the transaction fee, or one fixed fee for a stand-alone search |
What happens if two people search the same title?
Priority runs in order of search. If a second search with priority is made while the first is still running, the second applicant's priority is subject to the first's, and the certificate on the second search gives notice of any earlier official search with priority entered on the day list whose priority period has not expired. Practice Guide 12 sections 4 and 5.3, checked 20 September 2026. In an ordinary purchase this is the buyer and the buyer's lender, and one search made on the lender's behalf protects both. In a contested situation, two would-be buyers, or a creditor moving against the seller, whoever searched first wins the race, provided they lodge in time.
The search protects the disposition it names and nothing else. A search for a purchase does not protect a lease, and no search protects a charge lodged after priority has expired. Where the property is bought at auction, the short interval between exchange and completion makes the timing of the search more delicate still: it is made after exchange and before completion.