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Commercial Lease Law

Alienation Covenant in Commercial Leases — Assignment, Subletting and LTA 1988

Alienation covenant: controls tenant's ability to assign, sublet, part with possession, or share occupation of commercial premises. Absolute covenant: no dealing permitted; breach = potential forfeiture. Qualified covenant: dealing requires landlord's prior written consent; Landlord and Tenant Act 1988 applies. LTA 1988 statutory duties: landlord must (1) serve written decision within reasonable time; (2) consent unless reasonable grounds for refusal; (3) give written reasons if refusing; (4) not attach unreasonable conditions. Ashworth Frazer v Gloucester CC [2001] UKHL 59: reasonableness assessed at date of refusal; objective test; landlord bears burden of demonstrating reasonable grounds. Reasonable grounds for refusal: financial covenant weakness of incoming tenant; proposed use in breach of user covenant; material alterations without adequate protection; maintaining tenant mix. Conditions on consent: AGA from outgoing tenant generally reasonable; rent deposit; direct covenant with landlord. LTA 1988 s.4 damages: tenant entitled to damages for unreasonable refusal or delay — including loss of the proposed deal. Group company sharing: typically permitted without consent (licence not sublease); non-group sharing requires consent. Scotland: LTA 1988 applies only in England and Wales.

10 min readUpdated 7 June 2026Last reviewed: 17 May 2026alienation-covenantassignmentsublettinglta-1988

Absolute vs Qualified Alienation Covenants

Absolute covenant: no assignment, subletting, or sharing permitted; no right to seek consent; breach = potential forfeiture; uncommon in institutional leases. Qualified covenant: no dealing without landlord's prior written consent; LTA 1988 applies; consent must not be unreasonably withheld; landlord must give written decision with reasons. Fully qualified covenant: expressly states consent 'not to be unreasonably withheld or delayed' — LTA 1988 also applies; both contractual and statutory tenant protection. LTA 1927 s.19(1): pre-1988 Act leases — implied proviso that consent must not be unreasonably withheld where covenant is qualified. Absolute subletting with qualified assignment: some leases permit assignment (with consent) but prohibit subletting absolutely.

Landlord and Tenant Act 1988 — Statutory Duties

Four statutory duties where alienation covenant is qualified: (1) written notice of decision within reasonable time (typically 4–8 weeks for standard application); (2) give consent unless reasonable grounds for refusal; (3) written reasons if refusing (oral/informal refusal insufficient); (4) conditions must not be unreasonable. Time runs from receipt of application by landlord/agent — together with any supporting information reasonably needed. LTA 1988 s.4 damages: tenant can claim damages for breach of landlord's duties — including loss of the proposed deal, abortive costs, and consequential losses.

Reasonable Grounds for Refusing Consent

Ashworth Frazer v Gloucester CC [2001] UKHL 59: HL confirmed objective test for reasonableness; assessed at date of refusal; post-refusal events do not save unreasonable decision; landlord bears burden. Accepted grounds: financial covenant weakness of incoming tenant (insufficient net assets/trading history); proposed use in breach of user covenant; material structural changes without adequate protections; maintaining character of building or development (but must be applied consistently). Test: would a reasonable person in landlord's position have refused on those grounds, knowing what the landlord knew at date of refusal?

Conditions on Consent

AGA condition: requiring outgoing tenant to enter into AGA — generally accepted as reasonable condition under new leases. Rent deposit or additional security: reasonable where incoming tenant's covenant strength uncertain or lease for substantial term. Direct covenant: incoming tenant covenants directly with landlord to observe/perform lease covenants — standard and reasonable. Unreasonable conditions: conditions designed to extract premium or additional payment from incoming tenant; conditions restricting incoming tenant's use beyond existing user covenant — likely unreasonable under LTA 1988.

Sharing Occupation and Group Companies

Group company sharing: most commercial leases permit sharing with group companies (CA 2006 s.1159 — holding company/subsidiary relationships) without formal consent — provided no legal demise (sublease) is created; must be a licence to occupy. Non-group sharing: requires landlord's written consent unless expressly permitted. Creating a legal demise: formal sublease to group company requires consent even for group arrangements. Scotland: LTA 1988 applies only in England and Wales; Scottish commercial leases governed by Scots law; consent requirements and remedies differ; take specialist Scottish legal advice.

Frequently asked questions

What is an alienation covenant in a commercial lease?+

An alienation covenant controls the tenant's ability to assign, sublet, part with possession, or share occupation. It may be absolute (no dealing permitted) or qualified (dealing requires landlord's prior written consent). Where the covenant is qualified, the LTA 1988 imposes statutory duties on the landlord to respond within a reasonable time and not to withhold consent unreasonably.

What does the Landlord and Tenant Act 1988 require of landlords?+

Where the alienation covenant is qualified, the LTA 1988 requires the landlord to: (1) serve written notice of decision within a reasonable time; (2) give consent unless there are reasonable grounds for refusal; (3) give written reasons if refusing; (4) not attach unreasonable conditions. Breach entitles the tenant to damages including the loss of the proposed deal (LTA 1988 s.4).

What are reasonable grounds for refusing consent to assignment?+

Assessed objectively at the date of refusal (Ashworth Frazer v Gloucester CC [2001] UKHL 59). Reasonable grounds include: financial covenant weakness of the incoming tenant; proposed use in breach of the user covenant; proposed alterations without adequate protections. The landlord bears the burden of demonstrating that their grounds are reasonable.

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