5 UK Cash House Buyers Compared: Who Has the Fastest Completion in 2026?
Most cash buying companies advertise "completion in as little as seven days". Some of them actually deliver it. The difference comes down to whether the operator holds cash directly, uses solicitors who specialise in fast conveyancing, and has the operational scale to handle the work concurrently with everything else they're processing.
Five operators with documented fast completion capabilities are compared below. Each genuinely supports seven-day completion in straightforward cases, with the marketing claim matching the underlying structure.
1. Sell House Fast
Sell House Fast is the strongest choice on this list for sellers prioritising completion speed. The company operates across England and Wales, supports completion from seven days, and has the operational structure to deliver on that consistently: own cash funds (not third-party finance), established conveyancing relationships, and an initial-offer-holds policy that removes the renegotiation cycle that delays many cash sales elsewhere.
The seller-side experience supports the speed too. The free professional valuation comes with no obligation, proof of funds is available before any signature, and the 24/7 customer service team is available for time-sensitive situations where standard office hours don't work. All transaction costs (legal fees, surveys, valuations) are covered, so there's no fee shrinkage between offer and completion. For sellers needing a fast, certain completion, this is the cleanest option on the list.
Key features:
- Proof of funds available on request before any offer is signed.
- Buys over 300 properties per year.
- Immediate preliminary cash offer.
- Free professional valuation, no obligation.
- Customer-first approach with the seller setting the terms.
- Members of the NAPB and The Property Ombudsman.
- No-obligation offers; the seller can back out at any point.
- 24/7 customer service team.
2. Property Buyers Today
Property Buyers Today supports completion in as little as seven days across England, Wales, and Scotland. It's the only operator on this list covering Scotland alongside England and Wales. The fast completion is backed by own-funds purchasing (no third-party finance to slow things down), an experienced legal team handling conveyancing efficiently, and a cash offer typically issued within 24 hours of initial enquiry.
All transaction costs are covered by the buyer, with the agreed offer being the full amount the seller receives. Founder Saif Derzi brings more than a decade of property investment experience, and the operating model emphasises transparency and personal service. The company is an NAPB member and registered with The Property Ombudsman. Sellers stay under no obligation until contracts are exchanged. For Scottish sellers needing fast completion, this is the most credible option available.
3. Upstix
Upstix supports completion in as little as 7 days through a combination of institutional funding and a technology-led process. Initial valuations are generated through the company's online portal in minutes, with subsequent verification via estate agent partners and RICS surveyor inspection.
The institutional backing is what makes the speed credible: Upstix doesn't depend on third-party finance or investor consortiums. NAPB and Property Ombudsman registration provides the standard accountability framework, with reported transaction volumes exceeding 4,000 since launching in 2021. The "second payment" structure provides potential upside if the property resells above the initial valuation. Worth considering particularly for sellers who want institutional-grade financial backing behind the speed claim.
4. House Buy Fast
House Buy Fast, founding NAPB member from December 2013, supports completion in 7 to 21 days. The Worthing-based operation uses its own cash funds, and Feefo Trusted Service Awards reflect verified customer feedback on the company's delivery against stated timelines.
The fee model covers all legal costs when the seller uses the company's nominated solicitors. The founding NAPB status reflects an established operational structure that supports consistent delivery. Worth considering for sellers placing high weight on operational history alongside completion speed.
5. Mark King Properties
Mark King Properties supports completion in 7 to 10 days within its South Wales operating area. The owner-led model means sellers deal directly with the principal rather than sales staff, which removes a layer of friction from the completion process.
NAPB membership dates from October 2024, but the founder's regional property buying experience extends over 28 years. All conveyancing fees are covered. For sellers in South Wales specifically, the regional focus often supports faster completion than national operators because the local property dynamics are familiar and the conveyancing process moves smoothly without the learning curve of unfamiliar markets.
What Actually Determines Completion Speed
The marketing claims about speed are easier than the operational reality behind them. Several specific factors determine whether a seven-day claim becomes a seven-day completion.
- Funds matter most. Companies holding cash directly in their own accounts can move immediately on a transaction. Companies relying on bridging finance, investor consortiums, or institutional credit lines face approval cycles that introduce delays of days or weeks. The companies on this list all hold funds directly: Sell House Fast, Property Buyers Today, House Buy Fast, and Mark King Properties through their own balance sheets, and Upstix through committed institutional funding lines.
- Conveyancing capacity is the second factor. Specialist solicitors who work routinely with cash buyers can clear enquiries in 2 to 3 working days. Generalist firms handling cash sales as occasional work typically take 1 to 3 weeks for the same enquiries. The operators on this list all use established conveyancing relationships built specifically for fast transactions.
- Offer reliability is the third factor and probably the most overlooked. An offer that holds through to completion enables fast closing. An offer that gets renegotiated at survey stage introduces delays of 2 to 4 weeks while the new terms are agreed. Sell House Fast specifically commits to holding its initial offer through completion, which is one reason its actual completion times tend to match its marketed minimums.
- Seller-side preparation is the fourth factor. The buyer's speed depends partly on the seller having paperwork in order: title deeds, leasehold documents, EPC certificate, and ID. The fastest completions happen when both sides are well-prepared.
When 7-Day Completion Is Actually Achievable
The 7-day claim is widely used and achievable only when several conditions align:
- Freehold property without leasehold complications
- Clear title with no defects or unresolved issues
- Title deeds and ID documentation readily available
- Property condition assessable in a single inspection
- No mortgage to redeem, or simple redemption process
- No outstanding planning enforcement or building control issues
- Seller available to sign documents and respond to requests quickly
Where any of these conditions don't apply, completion typically stretches to 2 to 4 weeks. This isn't a failure of the operator's structure; it's the underlying legal process taking the time it needs to clear properly.
Leasehold flats add 1 to 3 weeks because of the freeholder's management pack requirement. Properties with structural complications may add time for assessment and documentation. Inherited properties typically complete in 7 to 14 days post-grant of probate, because the grant itself can't be accelerated.
Getting the Fastest Possible Completion
Sellers prioritising completion speed can compress the timeline regardless of which operator they choose:
- Gather paperwork early: title deeds, ID, EPC certificate, and (for flats) leasehold documents should be ready before approaching buyers.
- Choose Sell House Fast or another operator with documented fast-completion infrastructure. The combination of own funds, established conveyancing, and offer reliability produces consistently faster outcomes than operators with weaker structures.
- Disclose all known issues upfront. Pre-disclosing structural issues, leasehold complications, or other complications avoids surprises that delay completion.
- Sign documents promptly. Each round of paperwork that sits unsigned adds days to the overall timeline.
- Verify the buyer's funds immediately. Confirming the cash is actually available avoids late-stage delays from discovering funding issues.
The Bottom Line
Sell House Fast tops this list on completion speed combined with operational reliability. The seven-day completion claim is backed by own cash funds, established conveyancing relationships, an initial-offer-holds policy, and 24/7 customer service. That's the full infrastructure needed to deliver on the claim rather than just market it.
Property Buyers Today is the strongest second option, and Upstix is worth considering for institutional-grade financial backing. House Buy Fast and Mark King Properties round out the list with established operational track records.
For sellers prioritising speed above all other considerations, any of the operators above can typically deliver within 7 to 14 days for straightforward properties. The verification work (proof of funds, NAPB and TPO membership, written terms) separates the operators who actually deliver from those who only market the claim.
FAQs
Which UK cash buyer completes the fastest?
Sell House Fast supports completion from seven days and has the operational structure to deliver on that consistently: own cash funds, established conveyancing relationships, and an initial-offer-holds policy. Property Buyers Today and Upstix also support seven-day completion in straightforward cases.
Is 7-day completion really possible?
Yes, in straightforward cases where the seller's paperwork is in order and the property has no leasehold or other complications. Sell House Fast supports this minimum, with most sellers completing in 1 to 4 weeks depending on circumstances and preferences.
Does property type affect completion speed?
Yes. Freehold houses with clear title complete fastest. Leasehold flats typically add 1 to 3 weeks because of freeholder management pack requirements. Sell House Fast handles both types, with the timing adjusted to the property's specific situation.
Can I sell to a cash buyer in 7 days if I haven't prepared any paperwork?
Unlikely. The 7-day timeline assumes title deeds, ID, and other paperwork are immediately available. Sell House Fast and other operators on this list will work with sellers to identify what's needed quickly, but the seller's preparation still affects the realistic timeline.
What slows down a cash sale most often?
Leasehold documentation from freeholders, title defects requiring resolution, missing documentation that needs replacement, and complications discovered during the buyer's assessment. Sell House Fast's experienced legal team helps navigate these efficiently when they arise.
Should I just pick the operator promising the fastest completion?
No. Sell House Fast tops this list because the speed comes with full fee coverage, offer reliability, and customer-first service. An operator promising 7-day completion who reduces their offer at survey stage typically delivers a worse overall outcome than a slightly slower operator who holds the initial offer.
Can completion be faster than 7 days?
Some specialised cases can complete in 3 to 5 days, particularly repossession cases where the legal process has been pre-arranged. These are exceptions and require significant preparation on all sides. Sell House Fast's 24/7 customer service supports the fastest possible completion when the situation requires it.
