Air to Air Heat Pump Grant in Portsmouth

The grant position for a Portsmouth homeowner

Since 28 April 2026, an air-to-air heat pump qualifies for a flat £2,500 Boiler Upgrade Scheme (BUS) grant in England — Portsmouth included. That is the residential figure for air-to-air; it is not the £7,500 you may have read about, which applies only to air-to-water systems that also make hot water. On top of the grant, installation carries 0% VAT until 31 March 2027.

The honest catch for Portsmouth: the grant is only payable when the work is done by an MCS-certified air-to-air installer, and that certification route is still rolling out through 2026. Across Hampshire and the wider Solent, certified air-to-air installers remain thin on the ground, so the money is real but not yet easy to claim here. Check the detail on our eligibility page and MCS installers guide before you commit.

Why air-to-air fits so many Portsmouth homes

Portsmouth is unusual, and its housing is what makes the air-to-air case here stronger than in most cities. It is the most densely populated city in the UK outside London — around 208,000 people packed onto Portsea Island — and that density shows up as a housing stock of tight Victorian and Edwardian terraces, subdivided villas, and a large number of purpose-built and converted flats through Southsea (PO4, PO5) and inner PO1–PO3.

Air-to-water heat pumps need a hot-water cylinder and the airing-cupboard or loft space to put it. A great many Portsmouth flats and small terraces simply do not have that room. Air-to-air makes no hot water and needs no cylinder — it is wall-mounted indoor units fed by a compact outdoor unit — so for a one- or two-bedroom Southsea flat with an ageing storage heater or electric panel system, it is often the only heat pump that physically fits. That is the core local reason air-to-air deserves a serious look here.

• All-electric flats and conversions: homes on storage heaters or direct electric across PO4/PO5 gain both efficient heating and summer cooling, with no plumbing rework.
• Terraces on mains gas: most of Portsmouth's terraces are on the gas grid, so swapping a working gas boiler for air-to-air is roughly cost-parity on running costs — worth it mainly if you also want cooling, not as a money-saver. If you keep the gas boiler purely for a cooling add-on, you do not qualify for the grant.
• Off-gas fringe: a minority of homes toward Portsdown Hill and the PO6 edge, and older maritime properties, run on electric or bottled LPG rather than mains gas — for those, air-to-air replacing expensive off-gas heating is a genuinely strong financial case.

With an average house price around £235,000 — modest by South East standards and reflecting the small-footprint stock — many owners here are weighing a heat pump against a like-for-like boiler replacement, which is exactly where the £2,500 changes the maths. The full breakdown sits on our cost page.

Areas we cover around Portsmouth

This guidance applies across the city's postcode districts PO1, PO2, PO3, PO4, PO5 and PO6, and to the surrounding Solent conurbation where the same BUS rules and installer scarcity apply: Gosport, Fareham, Havant, Waterlooville and Southsea, extending toward Southampton and Chichester. The same £2,500-and-0%-VAT position holds throughout — you are in England, so the grant applies (unlike Scotland or Northern Ireland, which would get only the 0% VAT).

The council and local funding

Portsmouth City Council has set a 2030 net-zero target through its Portsmouth Climate Emergency Plan — one of the more ambitious dates among English unitary authorities. The council is also the delivery body for the Warm Homes: Local Grant, the means-tested successor scheme for lower-income and lower-EPC households; in practice that funding usually routes to air-to-water systems and insulation rather than air-to-air, but it is worth checking if you are on a low income or in a poorly-insulated property. The BUS £2,500 covered on this page is separate, is not means-tested, and stacks with 0% VAT. See grants and funding for how the schemes interact.

A realistic word on installers

Portsmouth sits within a competitive Solent installer market, but air-to-air specifically is the bottleneck. The trade here is dominated by gas engineers and air-to-water MCS firms; MCS-certified air-to-air capacity is only now emerging in 2026. Expect a short list and some waiting — and be wary of any firm quoting the grant without confirming its air-to-air MCS certification, because without it the £2,500 cannot be paid. We keep the honest picture up to date on our MCS installers page.

Is it right for your Portsmouth home? Quick check

• You likely qualify if you own a flat, conversion or terrace on Portsea Island heated by storage heaters or direct electric, or an off-gas home on the city fringe — and you use an MCS-certified air-to-air installer.
• You will not qualify if you keep a working gas boiler and just want to add cooling — the grant is for replacing your heating, not supplementing it.
• Remember air-to-air makes no hot water, so you will keep a separate source (immersion, existing cylinder or gas). Factor that into the sums on our cost page.

Next step: confirm you meet the conditions on eligibility, then read the grants and funding detail so you know what to ask a certified installer before signing anything.