Yes, for most homes in Leighton Buzzard, as long as yours is one of the many that nobody thought worth listing. The listed buildings cluster in the old centre. The town has no conservation area within its boundary. Hundreds of neighbours apply to build every year. The thing to worry about is the clay under the house.
Leighton Buzzard has 135 listed buildings. Two are Grade I, the top tier, three are Grade II*, and the other 130 are Grade II. On a listed building, almost any change that affects its character needs listed building consent on top of planning permission, and that includes inside work. Most of the listed stock is in and around the historic High Street and market square. The post-war semis and newer estates that make up most of the town are rarely on the list. If your house is a listed Georgian front on the High Street, the paperwork has been waiting for you longer than the house has been for sale.
The town's area also holds 4 scheduled monuments, the strictest protection tier, and they matter mainly to anyone whose land touches one.
Applications show how much of the town is being altered. Between April 2024 and June 2026, Central Bedfordshire received 1,085 planning applications for the area, 584 of them in the last twelve months. That is a town busily adding loft rooms, side extensions and garden rooms. The council's planning register lists every application, so you can see what the neighbours have already been through.
The ground is the part that catches people out. The British Geological Survey rates shrink-swell clay here at class 3, and every postcode in the town reaches that level. Clay at that level swells when wet and shrinks in dry summers, and that movement has to be allowed for in the foundations. For an extension that usually means deeper footings than a builder on dry, stable ground would dig, plus a structural engineer's view of nearby trees and drains. Ask the engineer for a trial pit early, because the depth of the foundations can change the budget more than the size of the extension does. Footings have to be dug for the clay in its driest summer, and a mild week when the builder is on site tells you nothing about that.
For an unlisted house, which is most homes in the town, smaller rear and side extensions and many loft conversions can often go ahead under permitted development rights, the national allowance for works that do not need a full application. Bigger or more prominent schemes need planning permission from Central Bedfordshire, and any listed building needs listed building consent whatever the size of the job. With no conservation area inside the town, the extra layer of control that comes with one does not apply here, although villages nearby such as Soulbury do have one. The same two-storey extension that sails through on a 1970s estate could become a long exchange of letters at a listed house on the High Street.
Your freedom to extend in Leighton Buzzard is about average. Most homes face few planning limits, the listed centre is the exception, and the clay adds cost everywhere in town.