Usually, yes, but in a good part of the town you'll need to ask first. More than a hundred buildings are listed. There are fifteen conservation areas. More than two thousand planning applications go in each year. The neighbours are extending, and they're doing it with paperwork.
Woking has 136 listed buildings: 2 at Grade I, 9 at Grade II* and 125 at Grade II. Listing covers the whole building, inside and out, so for any of them a new window, a knocked-through wall or a rear extension needs listed building consent on top of any planning permission. Most are Grade II, the most common tier, but Grade II still means the building's character comes before your plans for an open-plan kitchen. If the house you're viewing is on the list, the extension you're picturing is a proposal for a heritage officer to consider, not a plan.
There are 15 conservation areas in and around the town, including Horsell, Old Woking, Mount Hermon, The Hockering, St John's, Pyrford and Woking Town Centre, along with the Basingstoke Canal corridor. Inside one, the rules tighten for ordinary houses as well as listed ones. Changes to the front of a house, work on the roof, and demolition that would be routine a street away can all need consent. The estate agent will say "in a conservation area" as if it's a feature. For anyone planning an extension, it's a condition.
There are also 3 scheduled monuments in the area, the strictest tier of protection, including the Woking Palace moated site at Oldhall Copse and the barrows on Horsell Common. They mostly matter if your land borders one, and on a commons barrow that's unlikely.
None of this has stopped people. Between April 2024 and June 2026, 5,247 planning applications were submitted across the area, 2,340 of them in the last twelve months. That's the real evidence: people here extend, convert and rebuild constantly, and they do it through the planning system, not around it.
In practice, outside a conservation area and away from a listed building, many modest extensions and loft conversions can fall within permitted development, the national allowance for works that don't need a full planning application. Inside a conservation area, some of those allowances shrink or disappear, and for a listed building almost nothing is automatic. Before offering on a house because of what you'll add to it, check whether it's listed or in a conservation area, and look at what nearby houses have applied for. Neighbours' past applications show you what the council has been asked for, which is the closest thing to a preview of your own.
Freedom to alter a home is Woking's weak spot: plenty of work gets done, but in a sizeable part of the older town it happens only with consent.