Multiple Dwellings Relief (Abolished June 2024)

MDR abolished from 1 June 2024 by section 14 of the Finance (No. 2) Act 2024. Heavy abuse with HMRC winning ~80% of FTT cases drove the abolition. Six-or-more-dwellings rule remains. Linked transactions now aggregate at full SDLT.

The history of MDR

Multiple Dwellings Relief was introduced by Finance Act 2011, codified in Schedule 6B of the Finance Act 2003. The policy intention was to provide a fair SDLT calculation for purchasers of multiple residential dwellings in a single transaction, avoiding the harsh aggregate effect of taxing a portfolio purchase at the top marginal rate as though it were a single very expensive dwelling. The relief allowed averaging: SDLT was calculated on the average dwelling price across the bundle, then multiplied by the number of dwellings.

MDR worked well for genuine portfolio purchases: build-to-rent funds acquiring multiple flats in a single deal, family trusts buying small portfolios for the next generation, downsizers buying multiple small dwellings to spread investment. For these uses MDR was a fair and predictable tax treatment. However, MDR also worked spectacularly well for one specific abuse pattern: the “granny annex” argument, where a single house with a self-contained annex was treated as two dwellings, doubling the SDLT free amount available.

By 2020, MDR claims on properties with allegedly self-contained annexes had become a substantial tax-avoidance market, with specialist firms offering “MDR audits” on properties recently purchased to identify retrospective claims. HMRC estimated that around £700m per year was at risk from MDR claims by 2022-23, the majority of it from claims on properties that did not genuinely contain multiple dwellings as commonly understood.

The granny-annex litigation and HMRC's response

The leading case is Fiander v HMRC [2021] UKUT 156 (TCC), in which the Upper Tribunal set out the test for whether a property contains multiple dwellings: each dwelling must have its own facilities (kitchen, bathroom, sleeping accommodation) and be capable of being occupied independently as a single dwelling. A self-contained annex with its own kitchen, bathroom, and bedroom can be a separate dwelling; a small studio with a kitchenette and sleeping area but shared bathroom access typically cannot.

Subsequent cases (Hyman, Doe, Mullane, Khatoun, Lynch) progressively tightened the test. By 2023 HMRC was winning approximately 80% of MDR claim challenges at the First-tier Tribunal, with the failure rate weighted heavily toward retrospective claims by buyers who had not originally identified the property as containing multiple dwellings. The pattern was unsustainable: HMRC was incurring substantial litigation cost while taxpayers were incurring substantial advisory and litigation cost, with the underlying tax base eroding.

The Spring Budget 2024 (6 March 2024) announced the abolition of MDR from 1 June 2024, with transitional rules for purchases already in train. Section 14 of the Finance (No. 2) Act 2024 enacted the abolition. The Treasury's rationale was that the cost of administering MDR (in litigation, enforcement, and the abuse market) had grown to exceed the value of the relief to genuine portfolio buyers, and that the abuse was systemic rather than amenable to targeted anti-avoidance rules.

Transitional rules

The abolition took effect from 1 June 2024 with two main transitional protections. Transition A: contracts exchanged on or before 6 March 2024 (Budget Day) with completion on or before 31 March 2025 retained MDR. The 12-month grandfathering window protected buyers who had committed before the abolition announcement. Transition B: contracts substantially performed or completed on or before 31 May 2024 retained MDR. The day-before transition prevented MDR being clawed back from buyers in the final days of the regime.

Outside the transitional protections, all multi-dwelling purchases completing on or after 1 June 2024 pay SDLT without MDR. This applies regardless of when the contract was negotiated or exchanged, provided exchange was after 6 March 2024 or completion was after 31 March 2025 for the Transition A timeline.

Retrospective MDR claims for completed transactions filed under the standard 12-month amendment window before 1 June 2024 remain valid, subject to HMRC's normal enquiry rights. Many of these retrospective claims have been contested by HMRC since 2024 with the same approximately 80% HMRC-win rate as pre-abolition cases.

What remains: the six-or-more dwellings rule

The section 116(7) Finance Act 2003 rule treating a single purchase of six or more separate dwellings as non-residential SDLT remains in force. This rule was not abolished alongside MDR. So a build-to-rent fund acquiring six or more flats in a single transaction continues to pay non-residential SDLT (0/2/5%) on the aggregate price, with no additional-dwellings surcharge and no non-UK-resident surcharge.

The six-or-more rule is not subject to averaging; it simply applies non-residential rates to the aggregate price. For a portfolio purchase of 6 flats at £200,000 each (£1.2m total), the non-residential SDLT is £49,500 (0% on £150k + 2% on £100k + 5% on £950k). The same purchase as residential with no surcharge would pay £61,250; with the 5% surcharge it would pay £121,250. So the six-or-more route saves £11,750 against residential standard or £71,750 against residential surcharge.

The six-or-more rule is a structural advantage for portfolio buyers above the threshold but no help for buyers of 2-5 dwellings. Post-MDR-abolition, the 2-5 dwellings category is the worst affected: previously these buyers could use MDR averaging; now they pay full residential rates on the aggregate (often with the additional-dwellings surcharge stacked).

The post-MDR SDLT cost for portfolio purchases

The cliff at 5 dwellings is sharp: 5 flats at £200k pay £93,750 post-MDR, but 6 flats pay £49,500 under non-residential rates. Some portfolio buyers are restructuring to acquire 6 dwellings instead of 5 to access non-residential SDLT.

Linked transactions in the post-MDR world

Where multiple dwellings are bought from the same vendor in separate but linked transactions (e.g. a buyer purchasing three flats in the same building over a 6-month period under a single negotiation), the linked-transaction rules in section 108 FA 2003 aggregate the consideration for SDLT band purposes. Each transaction is calculated as though the buyer paid the aggregate price, with the SDLT then apportioned by value.

Pre-MDR-abolition, linked-transaction aggregation made MDR particularly valuable: even with linked-transaction aggregation, MDR averaging gave a meaningful tax saving. Post-abolition, linked transactions are taxed at the full aggregate residential SDLT without averaging. The linked-transaction rules are themselves widely tested by HMRC, with arguments about whether sequential purchases of similar properties from the same vendor constitute genuine separate transactions or a single linked acquisition.

Buyers of 2-5 dwellings from a single vendor in 2024-2026 should structure carefully to either avoid linked-transaction treatment (substantially different transactions, separated in time, with separate funding and separate commercial logic) or accept the aggregate SDLT bill. The previous MDR-driven strategy of bundling purchases to access averaging is no longer available.

The retrospective MDR-claim market

A small market still exists for retrospective MDR claims on historic transactions (within the 12-month amendment window from filing). HMRC's win rate against such claims since 2024 remains around 80%, mainly because the underlying property facts rarely satisfy the post-Fiander test for separate dwellings. Specialist firms that previously promoted MDR claims have largely wound down operations or repositioned to other SDLT planning.

For buyers who genuinely acquired multiple dwellings in a single pre-1-June-2024 transaction with no MDR claim made at the time, the amendment window allows a claim to be made within 12 months of the original filing. The claim must satisfy the genuine-multiple-dwellings test, and HMRC enquiry is virtually guaranteed. The cost-benefit of such retrospective claims depends on the strength of the multi-dwellings argument; for a borderline case the litigation cost and risk often outweigh the potential refund.

Wider portfolio-purchase strategy in 2026

The post-MDR SDLT environment has shifted portfolio-purchase strategy in three ways. First, the six-or-more-dwellings non-residential route is now consistently the cheapest SDLT outcome for any portfolio purchase above the threshold, and many buyers structure transactions to qualify (e.g. by bundling a sixth small flat or sectioning a building into six self-contained units). Second, single-dwelling purchases on a buy-and-build strategy are increasingly preferred over portfolio acquisitions, because the SDLT cost is the same as before but the operational and management overhead is lower. Third, build-to-rent funds increasingly negotiate single-transaction acquisitions of new-build developments at six-or-more dwellings to lock in non-residential SDLT.

For pension-fund and institutional buyers above £25m of portfolio value, non-residential SDLT is the standard outcome regardless of the abolition. For smaller portfolio buyers (2-5 dwellings), the abolition has materially increased the SDLT cost of building a small portfolio, with knock-on effects on rental yields and the economics of small-scale buy-to-let investment.

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