Replacing a Toilet: What It Costs and How Long It Takes

Updated July 2026 · Emergency Plumber Chelsea

Repair or replace first? A toilet that keeps running, fills slowly, flushes weakly or drips from the cistern nearly always needs a part, not a whole new toilet. Fill valves, flush valves, siphons, cistern seals and pan connectors are all replaceable. Our guides on a toilet that keeps running, a weak toilet flush and a toilet not filling with water cover the usual faults. Replacement is the right answer when the pan or cistern is cracked, when the ceramic is badly stained or chipped, when parts for an old model are no longer made, or when you simply want a different style as part of a bathroom update.

What sets the cost. We do not quote a single figure for a toilet replacement, because the bill depends on the specific job. The main factors are the toilet itself, whether the new pan outlet lines up with the existing soil pipe, whether the water supply needs moving or a new isolation valve, the condition of the floor under the old pan, how easy the room is to work in, and whether you want the old toilet taken away. A standard close coupled toilet on matching connections is at the simple end. A wall-hung toilet in a renovated bathroom, with a frame, boxing and tiling, is at the other.

The toilet you choose. Toilets vary widely, from basic close coupled sets to designer wall-hung pans with soft-close seats and rimless bowls. The type also changes the labour: a close coupled toilet is quick to fit, a back to wall toilet needs a unit or boxing to hide the cistern, and a wall-hung toilet needs a steel frame built into a false wall. If you are still deciding, our guide to the types of toilet explains how each one works and where it fits best.

Matching the soil connection. The single biggest variable in a straight swap is whether the new pan meets the soil pipe where the old one did. Pans are made with outlets that go either through the wall or into the floor, and the distance from the wall to the outlet varies between models. A flexible pan connector bridges small differences. A bigger mismatch can mean altering the soil pipe, which adds time, and in an older house the soil pipe itself may be cast iron or old clay that needs care to connect to. Measuring the old toilet before buying the new one avoids most surprises.

What we find under the old toilet. Once an old pan comes up, the floor underneath is sometimes rotten, stained or uneven from years of slow leaks around the base. Small patches can be made good before the new toilet goes down, but a soft or damaged floor has to be repaired properly, or the new pan will rock and the seal will fail. Old pans set in mortar or screwed into a crumbling screed can also take longer to remove cleanly. We tell you what we find and agree anything extra before carrying on.

Concealed cisterns and wall-hung toilets. Replacing a pan on an existing back to wall unit or wall-hung frame is often quicker than people expect, as long as the new pan suits the existing frame and cistern. Replacing the frame or concealed cistern itself is a bigger job, because it means opening the boxing and tiling. If your concealed cistern is the problem rather than the pan, our guide to concealed cistern problems explains what can be fixed through the flush plate opening.

How long does it take to replace a toilet? A like-for-like close coupled toilet on matching connections is usually a job of two to three hours, including isolating the water, removing the old toilet, fitting and sealing the new one, connecting the supply and testing for leaks. Allow longer if the soil connection has to be altered, the floor needs repair, the isolation valve has seized, or a unit or frame has to be built. On any job that runs over three hours there is no call-out fee, which often covers a replacement that turns out to need extra work.

Period houses and mansion flats. In older Chelsea houses the soil pipe may be cast iron, the floor may be old timber boards over a void, and the existing toilet may be a low level or high level design that a modern pan does not line up with. In mansion blocks, the soil stack is usually shared, so any work on the connection has to be done carefully to avoid disturbing neighbours' drainage. If you want to keep a period look, low level and high level reproductions are available and suit high ceilings well. In a listed building, check before removing original sanitaryware; our guide to plumbing in listed buildings covers when consent may be needed.

Moving the toilet at the same time. Replacing a toilet in the same position is the cheaper route. Moving it means rerouting the soil pipe with the right fall, which is straightforward over a short distance during a renovation and harder the further you go from the stack. Where gravity drainage is not possible, a macerator toilet is an option, though it needs more care in use; see our guide to macerator and Saniflo problems. If the toilet move is part of a wider refit, our guide to new bathroom costs covers the bigger picture.

Can you replace a toilet yourself? A confident DIYer can swap a close coupled toilet on matching connections. The common mistakes are overtightening the cistern bolts and cracking the ceramic, leaving the pan connector poorly seated so it weeps, and fixing the pan on an uneven floor so it rocks and breaks the seal. In a flat, a slow leak at the pan connection can soak into the ceiling below long before you see it. If the connections do not line up, the floor is doubtful or the toilet is concealed, it is a job for a plumber.

Booking a toilet replacement in Chelsea. Call Emergency Plumber Chelsea on 020 3002 6667 to have a toilet repaired or replaced. We check the soil connection, the water supply and the floor first, tell you whether a repair would do, and give you a clear price before work starts. See our toilet repairs service for faults, or our bathroom plumbing service for replacements as part of a refit. We cover SW3, SW10, Knightsbridge, Sloane Square, South Kensington and Fulham.

Quick tips

• Try a repair first: most running or leaking toilets only need a new valve or seal.
• Measure the distance from the wall to the centre of the soil outlet before buying a new pan.
• Note whether the old pan outlet goes through the wall or into the floor.
• Ask for a new isolation valve on the cistern supply if the old one is stiff.
• In a flat, check for damp around the base of the old toilet before the replacement starts.

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