Commercial Lease Law

Waiver of Forfeiture — Commercial Lease UK

Waiver of forfeiture: landlord with knowledge of tenant's breach does unequivocal act treating the lease as continuing (typically accepting/demanding rent accruing after the breach) → right to forfeit for that breach is waived. Knowledge required: landlord (or agent) must know of the specific breach. Segal Securities v Thoseby [1963]: automated rent demand by uninformed employee constitutes waiver. Once-and-for-all breach (unauthorised assignment; subletting; change of use): waived = permanently lost. Continuing breach (failure to repair; prohibited use): accepting rent waives breach to date of acceptance; fresh right to forfeit immediately arises for continuing breach. Avoiding waiver: immediately stop automated rent demands; instruct accounts and managing agents; return tendered rent; do not act under the lease. s.146 notice: accepting rent after serving s.146 notice can waive the notice. Scotland: irritancy (not forfeiture); Law Reform (Misc Provisions) (Scotland) Act 1985.

10 min readUpdated 7 June 2026Last reviewed: 17 May 2026waiver-forfeitureforfeiturecommercial-leaserent-acceptance

How Waiver of Forfeiture Works

Waiver: landlord with knowledge of breach does unequivocal act treating lease as continuing. Classic act: accepting or demanding rent accruing after date of breach. Other acts: serving schedule of dilapidations; issuing rent proceedings (not possession); granting consent; carrying out repairs. Knowledge required: must know of the specific breach. Intention irrelevant: objective act treating lease as continuing = waiver regardless of intention. Segal Securities v Thoseby [1963]: automated rent demand by uninformed employee = waiver.

Once-and-For-All vs Continuing Breaches

Once-and-for-all breach (unauthorised assignment; subletting without consent; change of use; unauthorised alterations): occurs at a specific moment; once waived = permanently lost. Continuing breach (failure to repair; prohibited use; keeping pets in breach of covenant): persists day to day; accepting rent waives breach up to date of acceptance only; breach continues; fresh right to forfeit arises immediately. Critical distinction: classify breach correctly before accepting any rent. Take specialist legal advice.

Avoiding Waiver

On learning of breach: immediately notify accounts and managing agents — stop all rent demands and do not accept any rent. Written instruction to accounts: document the instruction in case of dispute. Return tendered rent: return by recorded delivery without cashing cheque; retain proof. No acts under the lease: no inspection notices; no repairs; no consents; no communications treating lease as continuing. Urgent legal advice: if automated demand already sent or cheque already cashed — seek urgent advice on whether waiver has occurred and whether fresh breach grounds exist.

Section 146 Notices and Waiver

s.146 LPA 1925 prerequisite for non-payment-of-rent forfeiture: must specify breach; require remedy (if remediable); allow reasonable time. Accepting rent after serving s.146 notice but before effecting forfeiture: can waive the notice itself — landlord must serve fresh notice. Non-payment of rent forfeiture: no s.146 notice required for commercial leases — but accepting rent after formal demand extinguishes arrears and right to forfeit for that demand. Remedy period and waiver must be carefully managed. Always instruct specialist commercial property solicitors before proceeding.

Scotland and Relief from Forfeiture

Scotland — irritancy (not forfeiture): conventional or legal irritancy (2 years non-payment). Acceptance of rent after breach capable of founding irritancy may waive right to irritate in Scotland. Law Reform (Misc Provisions) (Scotland) Act 1985: protects commercial tenants — landlord must give 'fair and reasonable' opportunity to remedy. Relief from forfeiture (England/Wales — distinct from waiver): s.146(2) LPA 1925; equitable discretion; typically granted on terms (payment of arrears/costs; remedy of breach). Sub-tenants: can apply for relief under s.146(4) LPA 1925 if headlease forfeited.

Frequently asked questions

What is waiver of forfeiture?+

Waiver of forfeiture occurs when a landlord, knowing of a tenant's breach that gives rise to the right to forfeit, does any act treating the lease as continuing — typically accepting or demanding rent accruing after the breach. The landlord's intention is irrelevant. Once waived, the right to forfeit for a once-and-for-all breach is permanently lost.

What is the difference between waiver of a once-and-for-all breach and a continuing breach?+

For a once-and-for-all breach (e.g., unauthorised assignment), waiver permanently destroys the right to forfeit for that breach. For a continuing breach (e.g., failure to repair), accepting rent waives the breach only to the date of acceptance — the breach continues and a fresh right to forfeit arises immediately.

What practical steps avoid waiver?+

Immediately on learning of a breach: notify accounts and managing agents to stop all rent demands and not accept rent; do not act under the lease; return any tendered rent without cashing; document all instructions; seek urgent specialist legal advice.

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Forfeiture of Commercial Lease — Re-Entry, Section 146 Notice and Relief from Forfeiture

Forfeiture is the right of a commercial landlord to bring a lease to an early end for breach of covenant — non-payment of rent allows immediate peaceable re-entry without a s.146 notice; all other breaches require a valid s.146 notice (LPA 1925) first. Waiver — accepting rent after knowing of a breach — destroys the right to forfeit. Relief from forfeiture available to tenants within 6 months of peaceable re-entry. Scotland: irritancy under Law Reform (Miscellaneous Provisions) (Scotland) Act 1985.

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Forfeiture of Residential Leasehold UK

CLRA 2002 s.168 requires FTT or court determination of any breach before a landlord can serve a s.146 notice on a residential long leaseholder. Ground rent arrears threshold (s.167), s.146 notice procedure, waiver of breach, relief from forfeiture, and why residential leasehold forfeiture rarely succeeds in practice.

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LPA 1925 Section 146 forfeiture notice guide for residential long leases: CLRA 2002 s.168 requirement that breach must be admitted or determined by FTT before serving s.146 on residential long leases; s.169 CLRA 2002 rent/service charge arrears threshold (£350, 3 years); relief from forfeiture (s.146(2) LPA 1925); distinction from AST possession; interaction with service charge disputes.

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