Replace a toilet when the porcelain is cracked, when leaks keep returning after repairs, or when it flushes badly even after the tank and drain are checked. A worn flapper, fill valve or supply line is a repair, not a reason to replace. A model that uses up to 6 gallons per flush is also worth replacing.
Which problems mean the toilet needs replacing?
Cracks in the porcelain. This is the one sign that points straight to replacement. American Standard's support site says that if you find a crack or hairline fracture in the tank or bowl, "it is best to replace the toilet to prevent the crack from spreading, breaking and leaking water." A crack that leaks is a sign the part has reached the end of its life, so do not wait for it to get worse.
Sometimes only the tank is cracked. The same support site says "a toilet tank and / or toilet bowl can be replaced individually without having to replace the entire toilet," but only if the specific or compatible tank and bowl models are available. If the model is old or discontinued, ask whether a matching tank exists before you count on a tank-only fix.
A leak you cannot stop. Most leaks are cheap to fix, and you should try those first. EPA's leak guidance walks through the dye test and a flapper swap first. Then it adds that if you "find these step-by-step solutions aren't enough to stop them, it might be time to replace your leaking fixtures." A leak that persists after a new flapper, a new fill valve and a reset at the floor is the kind it means.
A rocking toilet that will not settle. A toilet that rocks is usually a floor or flange problem, not a bad toilet. Our guide on why a toilet rocks and how to fix it walks through it. Replacement only enters the picture if the bowl itself is cracked or the base is damaged.
A weak flush that never improves. Repair the flush first. Kohler's troubleshooting guide for a poor flush lists these checks:
- Remove slack from the trip lever chain.
- Match the water level to the waterline mark in the tank.
- Clean the rim holes under the bowl rim.
- "Clear any obstructions from the toilet bowl trapway or jet."
- Clear any obstructions from the waste line.
- Use a plunger and auger to clear blockage from the trap and waste line.
If you have done all of that and the toilet still flushes badly, or clogs again within days, the bowl design may be the limit. Our guides on why a toilet won't flush all the way and why a toilet keeps clogging cover the fixes in more detail. A toilet that clogs again and again can also point to a drain problem. That is a job for a plumber to look at before you spend anything on a new bowl.
Which problems are just repairs?
Many things that feel like a dying toilet are small parts. Replacing them is much easier than replacing the toilet.
- A toilet that runs or refills on its own. EPA says "most toilet leaks are due to old or worn-out toilet flappers." It calls the flapper an inexpensive part and says the flapper "should be checked periodically and replaced at least every five years to ensure a good seal and avoid leaks." Our guide on how to fix a running toilet and the one on how to replace a toilet flapper or fill valve show how.
- A tank that will not fill. See why a toilet tank is not filling. Kohler's no-flush chart starts with the easiest check: "Fully open the water supply shut-off valve."
- A handle that sticks. See how to fix a toilet handle that is loose or stuck.
- A supply line or shut-off valve that drips. See how to replace a toilet supply line and how to replace a toilet shut-off valve.
To check for a silent leak, EPA suggests putting a few drops of food coloring in the tank. "If any color shows up in the bowl after 10 minutes, you have a leak." Flush right after the test so the dye does not stain the tank.
Does the age of the toilet matter?
It can, because older toilets use much more water. EPA says toilets are "by far the main source of water use in the home," accounting for nearly 30 percent of an average home's indoor water use. It adds that "older, inefficient toilets that use as much as 6 gallons per flush" are a major source of wasted water in many homes.
Today's toilets are far lower. EPA says WaterSense labeled toilets use 1.28 gallons per flush or less, which is 20 percent less than the current federal standard of 1.6 gallons per flush. The 2024 International Plumbing Code also sets a maximum of 1.6 gallons per flushing cycle for a water closet in its fixture table, so a new toilet you buy today has to meet that limit. EPA reports that by replacing old, inefficient toilets with WaterSense labeled models, "the average family can reduce water used for toilets by 20 to 60 percent." Your own result depends on the toilet you have now and how many people use it.
Age alone is not a reason to replace a toilet that works. An older toilet that flushes well, does not leak and has no cracks can keep going. Age matters more when it comes with a high flush volume, or with repeated repairs. To find your toilet's flush volume, check the owner's manual or look up the model number on the maker's website.
Some utilities help with the cost. EPA notes that "in many areas, utilities offer rebates and vouchers" for WaterSense labeled toilets. Check with your water provider before you buy, since programs change.
What should you check before you buy a new toilet?
A few measurements and checks prevent the most common mistakes.
- 1Measure the rough-in. Korky explains that the rough-in is the distance from the toilet bolts to the wall behind the toilet. Korky adds that the standard rough-in is 12 inches, but some are 10 or 14 inches. Measure yours and buy a toilet made for that number.
- 2Check the space. The 2024 plumbing code says a water closet cannot be set closer than 15 inches, center to side wall or other obstruction, and needs at least 21 inches clear in front. Our page on how much space a toilet needs covers this in detail, and Korky notes that if you have a narrow bathroom, a round bowl might suit it better than an elongated one.
- 3Pick the style. Height, bowl shape and flush type change how the toilet feels in daily use. See our guides on comfort height versus standard height, skirted toilets and how a dual flush toilet works.
- 4Look at the flange and the shut-off valve. Korky says to inspect the flange for cracks or defects, and if you find any, "you must replace it with a new flange." Kohler's installation guide adds that if the existing toilet does not have a supply shut-off valve below the tank, you should install one before installing the new toilet.
- 5Do not open the box until you are sure. Korky warns that stores do not allow returns of toilets once a customer opens the packaging for sanitary reasons.
Toilets are heavy and porcelain chips easily. Korky recommends having help when you lift one. Our page on what a toilet replacement costs explains what goes into the price, and if the flange turns out to be damaged, see how to fix a broken toilet flange.
Not sure whether your toilet is worth saving? HQ Plumbing and Air can look at it and tell you straight, whether that means a small repair or a new toilet. We are licensed and insured, we give free estimates, and we quote the price up front. If you are also trimming water use, conserving water inside your home shows where a new toilet fits among the other fixtures.