Class MA Permitted Development: Converting Commercial Property to Residential in 2025/26

Why Class MA matters more than ever in 2025/26

If you're a UK property developer looking at empty shops, tired offices, or under-used commercial premises on your local high street, you should understand Class MA permitted development. Since 5 March 2024, the rules have changed in a way that significantly opens up commercial-to-residential conversions for small developers — the previous 1,500 m² floorspace cap was removed, and the requirement for the building to have been vacant for three months was scrapped. The result is that thousands more buildings are now eligible to be converted to flats without going through full planning permission.

For developers, that means faster project timelines, lower planning risk, and the ability to compete for sites that would previously have only suited large developers with the appetite for a full application. But Class MA still has teeth — get the eligibility checks wrong and you can lose months of programme on a refused prior approval. Here's what you need to know before you offer on a commercial site.

What is Class MA?

Class MA of Schedule 2, Part 3 of the Town and Country Planning (General Permitted Development) (England) Order 2015 (as amended) grants permitted development rights for the change of use of a building from Class E (commercial, business and service) to Class C3 (dwellinghouses). Class E is a broad use class introduced in September 2020 that covers shops, offices, restaurants, cafes, gyms, nurseries, and most light industrial uses on a high street.

In practical terms, this means you can convert almost any shop, office, restaurant, or similar commercial unit into flats or houses — as long as the building meets the eligibility tests and you secure prior approval from the local planning authority.

Eligibility — does your building qualify?

Before you offer on a Class MA site, run through this checklist. The building must:

• Have been in Class E use for a continuous period of at least two years immediately before the date of the prior approval application. Mixed use during that period is fine if Class E was the primary use, but a recent change to Class E from another use class can disqualify the building.
• Not be a listed building — Class MA does not apply to listed buildings, and you'll need full planning and listed building consent.
• Not be in certain protected areas — National Parks, the Broads, AONBs (now National Landscapes), Conservation Areas (in some cases — see below), and World Heritage Sites have restrictions or exclusions.
• Not be in an Article 4 Direction area that removes Class MA rights. Many councils introduced Article 4 directions specifically to block office-to-resi conversions in town centres — always check the local planning authority's policy map.

One common pitfall: in Conservation Areas, ground-floor retail or restaurant premises (formerly Class A1, A2, A3) are excluded from Class MA. So a typical above-shop conversion in a conservation area cannot use Class MA for the ground floor.

The prior approval process

Class MA is not a free pass — you still need to submit a prior approval application to the local planning authority. The council has 8 weeks (sometimes extended) to determine the application. Unlike full planning permission, the council can only refuse on a defined list of matters:

• Transport and highways impact — particularly parking provision and access
• Contamination risk — common on former industrial sites
• Flood risk
• Noise impact from neighbouring commercial uses (a key issue if you're converting a flat above a pub or takeaway)
• Adequate natural light in habitable rooms (introduced in 2021 — every habitable room must have a window providing adequate natural light)
• Provision of toilets and drainage
• Impact on the sustainability of the local shopping area (where the building is in a conservation area or designated shopping frontage)
• Fire safety impacts, if the building is 18 metres or more in height

Critically, the council cannot refuse on grounds of design, density, affordable housing provision, or general planning policy. That's a huge risk reduction compared to full planning.

Nationally Described Space Standards

Since April 2021, all Class MA conversions must comply with the Nationally Described Space Standards (NDSS). That means each new flat must meet minimum gross internal floor areas:

Dwelling Type	Minimum GIA
Studio (1 person)	37 m²
1-bed (2 person)	50 m²
2-bed (3 person)	61 m²
2-bed (4 person)	70 m²
3-bed (4 person)	74 m²

This is the rule that catches out the most developers. Older office floor plates often don't divide neatly into NDSS-compliant flats, and you can end up with awkward circulation, dead corners, or fewer flats than your appraisal assumed. Always sketch a proposed layout against NDSS before paying a deposit.

Worked example: above-shop conversion

Let's appraise a typical small Class MA scheme. You're looking at a vacant Class E unit on a secondary high street: ground-floor former estate agent (180 m² GIA) plus a redundant first-floor office (160 m²). Total 340 m². Asking price £325,000.

Line Item	Amount
Purchase price	£325,000
SDLT (commercial rates apply on mixed/non-resi)	£11,000
Legals + survey	£5,500
Prior approval application + planning consultant	£4,500
Build cost (340 m² conversion at £1,400/m²)	£476,000
Contingency (12.5%)	£59,500
Professional fees (10%)	£47,600
Finance, fees, selling costs (estimated)	£62,000
Total Costs	£991,100
GDV — 4 × 1-bed flats at £235,000	£940,000
Gross Profit (loss)	–£51,100

The deal doesn't work at this purchase price. You'd need to negotiate to around £270,000 — or find a fifth flat in the layout — to hit a 20% margin. This is exactly the kind of analysis that needs to happen before you commit to the prior approval fees and legals.

Practical takeaways

1. Always check Article 4 Directions first. Many councils have specifically blocked Class MA in town centres. A 30-second check on the council's planning portal can save weeks.
2. Verify the two-year Class E history. Ask the seller for evidence — business rates records, lease history, or HMRC correspondence.
3. Run the NDSS layout test before offer. If you can't fit four NDSS-compliant flats into the space, your appraisal is wrong.
4. Budget realistically for noise mitigation. Above takeaways, gyms, and pubs you'll need acoustic glazing and ventilation strategies that add £3,000–£8,000 per flat.
5. SDLT can work in your favour. Mixed-use commercial purchases qualify for non-residential SDLT rates, which are significantly lower than the residential additional dwelling rate.

Stress-test the deal before you commit

Class MA conversions can be highly profitable — but they fail when developers underestimate either the build cost (commercial-to-residential conversions are often heavier than expected) or the unit count their layout will actually achieve. Marginly's free deal appraisal calculator lets you model a Class MA scheme in minutes, with separate inputs for purchase, SDLT (commercial rates if applicable), build cost per m², contingency, finance, and selling costs — so you can see whether the numbers stack before you commit a penny in fees.