Renters' Rights Act 2025, Phase 1 commencement
Transition readiness pack

Commercial Property Law

Commercial Lease Rent Review UK — Upward-Only Reviews, Open Market Value, and Review Disputes

Covers types of rent review mechanism (upward-only open market; RPI/CPI-linked; turnover; fixed uplift; collar and cap); the open market review assumptions and disregards (vacant possession; tenant improvements; LTA 1954 s.34 basis); trigger notices and time-of-the-essence traps; counter-notice default; and dispute resolution by expert determination (RICS) vs arbitration (Arbitration Act 1996).

16 min readUpdated 8 June 2026Last reviewed: 17 May 2026rent-reviewcommercial-leaseupward-onlyopen-market-rent

Types of Rent Review Mechanism

Open market review: the most common mechanism — rent reviewed to the open market rental value on the review date (willing landlord, willing tenant, hypothetical new letting on the same lease terms). Upward-only review: the rent can only increase or stay the same on review; cannot fall even if market rents decline; standard in UK institutional commercial leases and legal in England and Wales (prohibited for new Scottish commercial leases since 2009 under the Land Reform (Scotland) Act 2003). RPI/CPI-linked: automatic formulaic review; avoids valuation disputes; return tied to the index — may lag market rents. Turnover rent: base rent plus % of turnover above a threshold; aligns landlord income with tenant performance; common in retail and hospitality. Collar and cap: upward-only review with a minimum increase (collar) and maximum increase (cap); reduces volatility for both parties.

Open Market Review — Assumptions, Disregards, and Traps

Assumptions: premises vacant and available to let; lease on the same terms (less the rent review clause itself); willing landlord and willing tenant; premises fit for the permitted use. Disregards (LTA 1954 s.34 basis): any goodwill of the sitting tenant; improvements carried out by the tenant during the term at their own expense and not pursuant to an obligation to the landlord; fact of the sitting tenant's occupation. Time-of-the-essence traps: where the review clause makes the trigger notice deadline TotE, a late notice can forfeit the review for that period — the rent stays at the pre-review level until the next review date. Where TotE is not expressed, a late notice activates the review but the reviewed rent runs only from the date of the late notice — Drebbond Ltd v Horsham DC (1978). Counter-notice default: failure by the tenant to serve a counter-notice within the specified period can result in the landlord's proposed rent being accepted by default.

Dispute Resolution — Expert Determination vs Arbitration

Expert determination: the expert (RICS-qualified surveyor) acts on their own expertise; not bound to decide solely on submitted evidence; decision binding except for manifest error or fraud; most common for commercial rent reviews. Arbitration: governed by Arbitration Act 1996; decided on the evidence submitted by the parties; challengeable on limited grounds (serious irregularity; error of law); arbitrator's costs discretion. Calderbank offers: in arbitration, either party can make a costs-protecting offer — if the award beats the offer, the offeree may pay costs from the offer date. RICS appointment: either party can apply to RICS to appoint an expert or arbitrator if the parties cannot agree. Diarise all review trigger notice deadlines with a 3-month lead time; instruct specialist commercial property surveyors for review negotiations.

Found a gap or disagree with something?

Reply to any LetSafe email or write to Richard@letsafeuk.co.uk. We rewrite guides when we get something wrong, the sooner we hear, the sooner we fix it.

Hand-picked by topic overlap with this guide.

Commercial Property
Rent Review Dispute UK — Arbitration, Expert Determination, and the Time-of-the-Essence Trap
What happens when landlord and tenant cannot agree on the reviewed rent — RICS arbitration vs expert determination, the Starmark time-of-the-essence trap, and how comparables evidence is used.
Commercial Property Management
Commercial Service Charges for Landlords UK
Commercial service charge in multi-let commercial buildings: contractual basis (not statutory LTA 1985); RICS Code of Practice for Service Charges in Commercial Property (3rd edition, 2018); recoverable costs (management fees 10–15%; maintenance; insurance; utilities; sinking fund); excluded costs (latent defects; improvements; void unit costs); certification by qualified accountant within 4 months of year-end; sinking fund on trust; caps and collars; dispute resolution: expert determination; RICS arbitration (no FTT jurisdiction for commercial).
Commercial Lease Incentives
Rent-Free Period in Commercial Leases UK
Rent-free period in commercial leases: fit-out period (3-6 months at lease start to allow tenant to make premises operational) vs headline incentive (additional market incentive). During rent-free: service charges, insurance, and business rates typically still payable. HMRC spreading: landlord must spread total rental income evenly over full lease term — rent-free does not create nil-income period (ITTOIA 2005/CTA 2009). Effective annual rent for tax = total rent ÷ lease years. Rent review interaction: headline rent vs effective rent; whether rent review assumes rent-free period depends on review clause assumptions and disregards. Scotland: same HMRC spreading treatment; LBTT NPV calculation excludes rent-free period.
Commercial Insolvency
Insolvency Disclaimer of Lease UK — Liquidator Powers, Guarantor Liability, and Vesting Orders
Understand how IA 1986 s.178 disclaimer works, why guarantors are not released (Warnford v Duckworth), how subtenants apply for vesting orders under s.181, and how landlords rank as unsecured creditors after disclaimer.
Commercial Property Law
Dilapidations Commercial Lease UK — Terminal Dilapidations, the s.18 Cap, Scott Schedule, and Break Clauses
Covers terminal vs interim dilapidations; the Jervis v Harris clause (cost recovery as a debt during the term); Scott Schedule process and RICS Protocol; LTA 1927 s.18(1) diminution in value cap and supersession (Ultraworth [2000]); and the critical interaction between break clauses and dilapidations compliance conditions.
Commercial Property Law
Commercial Lease Guarantor UK — AGA on Assignment, Guarantee Provisions, and PCO Obligations
Covers types of guarantee in commercial leases (corporate; personal; rent deposit; AGA); the LT(C)A 1995 framework for post-1995 Act leases; AGA mechanics and the one-deep guarantee chain; s.17 fixed charge notice within 6 months; overriding lease right under s.19; guarantee caps; and enforcement steps against corporate and personal guarantors.