Auction Property Glossary: Every Term You Need to Know
UK property auctions have their own vocabulary. Understanding the terminology before you attend helps you follow proceedings confidently — and ensures you don't misunderstand anything that affects your legal position.
A
Addendum — A document issued by the auction house on or shortly before auction day that records last-minute changes to the catalogue: withdrawn lots, amended guide prices, corrected legal information, or new special conditions. Always read the addendum before bidding.
Agreement for sale — The legally binding contract exchanged when the hammer falls at a traditional auction. Also called the memorandum of sale.
B
Below market value (BMV) — A purchase price lower than the property's open market value. Typically expressed as a percentage: a 20% BMV deal means you're paying 20% less than the estimated market value.
Bidder registration — The process of registering with the auction house before you can bid. Requires photo ID and, increasingly, proof of funds. Usually completed on auction day but some houses allow pre-registration.
Bridging loan — Short-term finance used to fund auction purchases, typically repaid within 6–18 months via sale or refinance. The most common finance vehicle for auction property given the 28-day completion requirement.
Building survey — A structural inspection of a property carried out by a RICS-qualified surveyor before purchase. Essential for properties in poor condition.
C
Catalogue — The list of lots in an upcoming auction, published by the auction house in advance. Usually available online and updated as lots are added, withdrawn, or amended.
Completion — The point at which the legal transfer of ownership is finalised and funds are transferred. In traditional auction, completion is typically 28 days after exchange.
Conditional auction — See Modern method of auction.
Conveyancing — The legal process of transferring property ownership. At auction, exchange happens instantly when the hammer falls; conveyancing then handles the completion.
D
Deposit — The sum paid immediately when the hammer falls at a traditional auction, typically 10% of the purchase price. Non-refundable if you fail to complete.
Due diligence — The research and checks carried out before bidding: reading the legal pack, viewing the property, assessing value, reviewing finance options.
E
Exchange — The point at which contracts become legally binding. At traditional auction, this is the moment the hammer falls.
G
Guide price — The indicative price published by the auction house to attract bidders. Not a valuation and not the same as the reserve price. The reserve can be set up to 10% above the guide price under RICS rules.
H
HMO — House in Multiple Occupation. A property occupied by three or more people from two or more households who share facilities. Subject to mandatory licensing above five occupants; local councils may extend licensing to all HMOs.
Hammer price — The price at which the auctioneer's hammer falls, indicating the winning bid. The legal purchase price at traditional auction.
L
Legal pack — The bundle of documents relating to a lot, made available by the auction house before the sale. Typically includes the title register, searches, lease documents (if leasehold), and special conditions of sale. Reading it is essential before bidding.
Lot — A single property or parcel of land listed for sale at auction.
M
Memorandum of sale — The contract signed by buyer and seller immediately after the hammer falls at traditional auction. Legally binding.
Modern method of auction — An auction format where the buyer pays a non-refundable reservation fee on the day, exchanges contracts within 28 days, and completes within 56 days. Allows more time for mortgage finance.
O
Online bidding — The ability to bid in real time via the auction house's website or platform. Legally equivalent to bidding in the room.
P
Passed in — A lot for which the reserve price was not met. The lot is withdrawn unsold. The buyer may be able to negotiate with the vendor after the auction.
Proxy bid — A maximum bid submitted in advance; the system bids on your behalf up to that limit.
R
Reserve price — The minimum price the vendor will accept, set confidentially before the auction. Under RICS guidance, the reserve cannot exceed 10% above the published guide price. If the reserve is not met, the lot is withdrawn.
S
Sale by private treaty — Negotiation after an auction when a lot has been passed in. Not bound by auction conditions.
Special conditions of sale — Additional contractual terms attached to a specific lot that override or supplement the standard auction conditions. These appear in the legal pack and can include unusual costs, restrictions, or requirements. Always read them.
Stamp Duty Land Tax (SDLT) — The tax payable on property purchases in England and Northern Ireland. Calculated on the purchase price. Payable within 14 days of completion.
T
Title register — The Land Registry record of ownership and any charges, restrictions, or covenants on a property. Included in every legal pack.
V
Vacant possession — The property is delivered to the buyer empty on completion — no tenants, no previous owner remaining in occupation. Standard at auction unless stated otherwise.
Vendor — The seller of the property.
W
Withdrawn — A lot that has been removed from the sale, either before auction day or because the reserve was not met on the day.
For more auction terminology, visit the BelowHammer glossary or browse live UK auction lots with AI-estimated values and profit analysis.