Do not assume the pan seal is the only cause
Water around the foot of a toilet can come from several places and then collect at the lowest point. A leaking inlet connection, cistern bolt, close-coupling seal or condensation on the cistern can all run down and appear around the base. Dry the toilet completely, then use it normally while watching the higher fittings first. If the floor stays dry until the toilet is flushed, the waste connection becomes more suspicious. If water appears while the cistern is filling, look towards the supply and cistern rather than the pan outlet.
A waste leak often has a particular pattern
A failed pan connector usually leaks when a flush sends a large volume of water into the soil pipe. The amount may be tiny at first, especially if the connector only moves slightly when somebody sits down. There may also be an unpleasant smell if the seal is not sound. A toilet that rocks on the floor can strain the connector and make the problem return even after a new seal is fitted. The stability of the pan therefore matters just as much as the rubber connection behind it.
Other water can mimic a base leak
Condensation is common on cold cisterns in warm, humid bathrooms. Droplets form on the outside and run down the ceramic, leaving a puddle that looks like a plumbing leak. A faulty flush pipe on an older low-level cistern can do the same. On close-coupled toilets, the large seal between cistern and pan may leak only during flushing. Use dry tissue around each joint to identify the first wet area. That is far more reliable than judging the final puddle on the floor.
Why the floor condition matters
Water around a toilet can get beneath vinyl, laminate or tiled edges where it remains hidden. Chipboard flooring can swell and lose strength, while timber around old fixing holes can soften. If the pan has become loose, continuing to use it can enlarge the movement and make the waste seal worse. A persistent sewage smell, visible staining around the connector or a soft floor should move the repair higher up the list. The leak itself may be small, but damage to the subfloor can make the eventual job much larger.
How a plumber may repair it
If the waste connection is leaking, the toilet may need to be disconnected and moved forward so the pan connector can be replaced properly. Simply applying sealant around the visible base does not repair a failed waste seal. Supply leaks and cistern seals can often be reached without removing the pan. The plumber should also check that the toilet is sitting firmly and that the floor is sound enough to hold the fixings. If movement caused the original failure, stabilising the pan is part of the repair rather than an optional extra.
What helps when asking for a quotation
Explain whether the water appears all the time, only after flushing or mainly after the cistern refills. Mention any smell, rocking movement or damage to the flooring. A photograph from the side showing the waste connection is more useful than a close-up of the puddle alone. If the toilet is boxed in, say how much access there is. Quotes can vary because one contractor may expect a simple seal change while another has allowed for removing and refitting the toilet, so ask what the price includes.
Do not seal the toilet to hide the evidence
A bead of silicone around the foot of the pan can make a bathroom look neat, but it should not be used to conceal an unresolved leak. If the waste connection has failed, trapping water beneath the toilet can allow the floor to deteriorate without being noticed. Where the pan has to be removed, ask the plumber to inspect the condition of the floor and the alignment of the soil connection before refitting it. A toilet that rocks should be stabilised rather than simply tightened down onto an uneven surface. After the repair, flush several times and check the supply side as well as the waste side. If the floor covering has already lifted or softened, deal with that damage once you are satisfied the plumbing itself is dry.
This page is general guidance about toilet leaking at base; the cause in an individual home still needs to be established from the actual installation.