Yes, and more freely than in almost any similar town. Only three listed buildings across the whole town boundary. No conservation area anywhere within it. A single scheduled monument, sitting well away from residential streets. The heritage regulator has, by and large, left this town to itself.
Three listed buildings in a settlement of about 10,000 people is a very low count. None sit at Grade I, which is where the country's most significant buildings live. Two are Grade II star, a status reserved for buildings of particular importance beyond ordinary listing, and one is standard Grade II. What that means for a homeowner is that unless your specific address is one of those three, you are not dealing with listed-building consent at all. Listed-building consent, for anyone who has not run into it before, is the parallel planning process that governs any alteration to a listed structure, including internal work, and it is the step that turns a straightforward rear extension into a six-month conversation with a heritage officer. In Polegate, that conversation is being had, on paper, at only three addresses. Everyone else is playing the ordinary planning game.
Practically, that means the standard permitted-development regime applies to almost every home. Single-storey rear extensions, loft conversions with dormer windows, side extensions within the household's own boundary, small outbuildings, and modest changes to the front elevation are broadly the jobs that can be done without applying for planning permission at all, provided they fit within the size and material limits set nationally. Anything bigger, or anything that changes the shape of the house at the front, still needs a formal planning application to the local authority. Without a conservation area, though, there is no Article Four direction removing those permitted-development rights, which is the thing that catches out buyers in the prettier postcodes elsewhere in the county. The one scheduled monument in the town is a protected feature rather than a house, so unless a homeowner is minded to build directly onto it, it is not the constraint that matters here.
Above average for extension freedom at four out of five. If you want a house with soul and a listed-building consent stapled to every job, buy in one of the historic villages the wider area covers. If you want a post-war house and a rear extension without a heritage officer weighing in, Polegate does that as well as anywhere.