Mostly yes, as long as your house isn't one of the old ones in the middle. Listed buildings are few and clustered. Three conservation areas cover the historic parts. Everywhere else, the planning office is dealing with ordinary homes and ordinary extensions. The paperwork follows the history, and most of New Romney doesn't have much of it.
Historic England's list records 64 listed buildings in the area: one at Grade I, two at Grade II* and 61 at Grade II. Listing covers the whole building, inside and out, and any change that affects its character needs listed building consent on top of any planning permission. That includes things owners assume are routine, like replacing windows, removing an internal wall or changing a roof covering. Carrying out works without consent is a criminal offence, not a planning technicality, so "the previous owner did it" is a line to check before exchange, not after.
There are three conservation areas here: New Romney High Street, New Romney Cannon Street and Littlestone-on-Sea. Inside them, the council has more say over how buildings look from the street, and demolition, some extensions and changes to trees can need consent that an identical house outside the boundary would not. The Cannon Street and High Street areas cover the old core of the town; Littlestone's covers the seafront the Victorians laid out as a resort. If a listing describes a house as "full of character", find out which side of those boundaries the character sits.
Two scheduled monuments fall within the area, the strictest tier of heritage protection. They matter mainly for anyone buying land near one, where groundworks can need separate consent.
The neighbours are not waiting for permission to stop being difficult. The local planning register holds 307 applications between April 2024 and June 2026, with 143 of them in the last twelve months. That is a steady flow of people building conservatories, rear extensions and new porches in a town where most homes carry no heritage designation at all. The volume is the evidence: altering a house here is normal, not a campaign.
In practice, the answer depends on which kind of house you buy. An unlisted home outside the conservation areas can often use permitted development rights for modest rear extensions and outbuildings without a full application, subject to the national limits and the council's view on the details. A listed building, or a home inside one of the three conservation areas, starts from the opposite position: assume you need consent and check before drawing anything. Either way, ask the council before paying an architect, because an hour on the phone costs less than a refused application.
Your freedom to alter a home here is middling: easy for the ordinary post-war house, slow and expensive for the historic core. Choose the house for the extension you actually want, not the one you hope to talk the council into.