Close-coupled, low-level, high-level and back-to-wall toilets compared

Most UK toilets work in the same basic way: a cistern holds water, a flush valve or siphon releases it into the pan, and a fill valve refills the cistern. What differs is where the cistern sits and how it is joined to the pan. That decides which parts you need, how easy a repair is, and what to look for when replacing a toilet.

This guide compares the common styles. For fixing a toilet that keeps running or will not refill, see our guides to a running toilet and toilet fill and flush valves.

Close-coupled

The most common style in UK homes. The cistern sits directly on the back of the pan, bolted to it, with a large rubber or foam doughnut seal between them where the water passes through.

What it means for repairs:

• Lift the lid and everything is in reach.
• The cistern is fixed to the pan with cistern-to-pan bolts, each with a washer. A drip from under the back of the cistern is often one of these bolts or the doughnut seal.
• Changing the flush valve or siphon usually means separating the cistern from the pan: draining it, undoing the bolts and lifting it off. Use a new doughnut seal when you put it back.
• Pans and cisterns are usually sold as a matched pair. A cistern from one range rarely fits another maker's pan properly.

Low-level

A low-level toilet has the cistern mounted on the wall a short way above the pan, joined to it by a short flush pipe. It is common in older homes and in traditional-style bathrooms.

What it means for repairs:

• The cistern is separate, so the flush valve can usually be changed without moving the pan.
• The flush pipe connects to the pan with a flush pipe cone or connector, a rubber seal pushed into the pan's inlet. A leak where the pipe meets the back of the pan is often this cone, which perishes with age.
• Many older low-level cisterns use a siphon, operated by a lever. Parts are widely available, but measure the existing ones before buying.

High-level

A high-level toilet has the cistern high on the wall, often near the ceiling, with a long flush pipe and a pull chain. It is a Victorian design, still sold for period bathrooms.

What it means for repairs:

• The cistern needs safe access at height: use a stable stepladder and have someone with you.
• High-level cisterns usually use a siphon worked by the chain. Old cast iron cisterns may need specialist parts; modern reproduction ones use standard parts.
• The cistern must be firmly fixed. A loose bracket on a heavy cistern above head height is a hazard. Call a plumber if it moves.

Back-to-wall

A back-to-wall pan sits on the floor with its back flush against a wall or a furniture unit. The cistern is concealed behind the unit or a false wall, and the flush button sits on top of the unit or on the wall.

What it means for repairs:

• The cistern is hidden, so access is through a removable panel, the top of the unit, or the flush button opening. Check there is one before anything goes wrong.
• Concealed cisterns use specific fill and flush valves. Note the cistern brand and model when it is fitted.
• The soil connection is hidden behind the pan, so a leak may show only as a damp floor or a smell.

Wall-hung

A wall-hung toilet has no foot on the floor. The pan is bolted to a steel frame inside the wall, with the cistern built into the frame and a flush plate on the wall. It needs the most planning and is usually fitted during a refit. Our guide to wall-hung toilets explains the frame and access.

At a glance

Style	Cistern position	Link to pan	Typical access to valves
Close-coupled	On the pan	Doughnut seal and bolts	Lift the lid
Low-level	Low on the wall	Short flush pipe	Lift the lid
High-level	High on the wall	Long flush pipe	Lift the lid, at height
Back-to-wall	Hidden behind a unit	Concealed flush pipe	Panel or button opening
Wall-hung	Inside a frame in the wall	Short concealed connector	Flush plate opening

The soil connection

Every style connects the pan outlet to the soil pipe with a pan connector. Whether it is a straight, offset or angled connector depends on where the soil pipe is. A leak at the back of the pan after flushing may be at this connector rather than the cistern. Our guide to WC pan connectors explains how to tell clean-water leaks from waste-water leaks.

Replacing a toilet

When you replace a toilet:

• Measure the distance from the wall to the centre of the soil pipe, and where the water supply comes in, before you buy.
• Match the outlet of the new pan to the soil pipe position, or plan for a different connector.
• Check the supply entry for the cistern (side or bottom) suits your pipework.
• Fit an isolation valve on the supply if there is not one. See isolation valves.
• Changing styles (for example, close-coupled to wall-hung or back-to-wall) usually means changing pipework and walls. That is a bigger job, best done as part of a bathroom refit.

If the pan is cracked, the floor under it is soft, or the soil pipe is damaged, call a plumber.

Examples at Wickes

We haven't tested these. They are examples, with what the retailer's pages say.

We haven't tested this. Figures are as the maker states them (checked 13 November 2026).

What is the difference between close-coupled and low-level toilets?

On a close-coupled toilet the cistern sits directly on the pan. On a low-level toilet the cistern is on the wall a little above the pan, joined by a short flush pipe. That changes which seals can leak and how you reach the flush valve.

Can I put a different cistern on my close-coupled pan?

Usually not reliably. Close-coupled pans and cisterns are designed as a pair, with matching bolt holes and seal positions. Buy the cistern made for your pan, or replace both.

Why is water leaking from under my cistern?

On a close-coupled toilet, the usual suspects are the cistern-to-pan bolts and washers or the doughnut seal. On a low-level or high-level toilet, check the flush pipe cone where it enters the pan. If the leak only appears after flushing, also check the pan connector at the back.