Yes, and most of Andover will barely notice you doing it. There are 132 listed buildings in the area, only one of them at the top grade. Three conservation areas. Three scheduled monuments. The question is not whether extensions happen here, it is whether you bought a house or a heritage asset with a kitchen attached.
The national list of protected buildings covers 132 here: one at Grade I, six at Grade II star and 125 at Grade II. Listing covers the whole building rather than the front elevation people assume it stops at, which is why it catches windows, internal walls, a flue in the wrong place and the wrong sort of render. Listed building consent runs separately from planning permission, and the sequence that ends in tears is always the same one: work first, paperwork afterwards.
Three conservation areas sit inside the area, covering Andover itself along with Abbotts Ann and The Pentons. Designation does not freeze a place in amber, it changes who gets a vote. More alterations need permission, some of the rights you would otherwise use without asking anybody are narrower, and the disagreements tend to be about materials and proportion rather than whether you can build at all.
There are also three scheduled monuments in the area, which sit at the strictest protection tier of the lot. For a semi with a side return they are irrelevant. For anyone with land near one they are the whole conversation, because the constraint there is about disturbing the ground rather than what the extension looks like from the pavement.
What the neighbours are doing settles the question better than any policy document. Between April 2024 and June 2026, 2,060 planning applications were logged across the area, with 904 of those in the most recent twelve months. That is a place where the planning portal is a normal part of household life rather than a once-a-decade ordeal. What those counts do not tell you is how any individual one turned out, so treat them as evidence that people try, not as a promise about your own drawings.
Practically, the split is this. About 8% of dwellings on the council tax valuation list predate 1930, so the great bulk of the stock is post-war or later, and outside the designated areas that is where permitted development earns its keep: rear extensions, loft conversions, the side return everybody eventually builds, all sitting inside the national limits rather than a local negotiation. Inside a conservation area, or on anything listed, assume you are asking rather than announcing, and get the answer in writing before a skip appears on the drive.
Freedom to alter a house here is narrower than a street map full of post-war estates would suggest, because the protections cluster precisely in the parts of the area people point at when they describe it as pretty. Find out which side of a designation boundary your address falls on before you get attached to the drawings.