Why is my toilet running constantly and how to fix it
A toilet that runs constantly is almost always a worn flapper, a bad fill valve, or a stuck float. Here is how to diagnose and fix it in Suffolk, VA.
A toilet that runs constantly is almost always losing water past a worn flapper, a failing fill valve, or a float that never shuts the water off. In nine out of ten homes we service, the fix is a $12 to $30 part and under an hour of labor. The rest of this post walks through how to tell which part failed, how to replace it yourself, what a running toilet repair costs in Suffolk in 2026, and when it makes more sense to hand it to a plumber.
If you have ever stood in the hallway at 11 p.m. listening to your toilet hiss, you already know the sound. That hiss is water moving. Water moving is money leaving your account. A toilet running constantly in Suffolk VA is one of the most common calls we get, and it is also one of the easiest to stop once you know what you are looking at.
Why is my toilet running constantly in Suffolk VA?
A constantly running toilet in Suffolk is caused by water escaping the tank faster than the fill valve can shut it off, which keeps the valve cycling and the water flowing. That is the whole mechanism. The tank fills, the water level drops through a leak, the fill valve kicks back on, and the cycle repeats every few minutes for as long as the leak exists.
There are only four parts inside a standard gravity-flush toilet tank that can cause this: the flapper, the fill valve, the float, and the overflow tube. Every running toilet we diagnose in Suffolk traces back to one of those four. Sometimes two at once, especially on toilets that are 15 years or older.
Our local water here in Suffolk is treated surface water pulled largely from the Western Branch and the surrounding reservoirs. It runs slightly on the hard side, and hard water is rough on rubber. Flappers and valve seals in this area tend to fail faster than the manufacturer's five-year estimate. We routinely replace flappers on Suffolk toilets that are only three or four years old.
If you have already replaced a flapper once and the toilet started running again within a year, that is a sign of mineral buildup on the flush valve seat, not a bad flapper. Scraping the seat clean with a Scotch-Brite pad before installing the new flapper solves it. Skipping that step is why so many DIY flapper swaps fail the second time.
The four parts that cause a constantly running toilet
Pull the tank lid off and look inside. You will see the same four components on almost every toilet made in the last 40 years. Here is what each one does and how it fails.
The flapper
The flapper is the rubber seal at the bottom of the tank that lifts when you press the handle and drops back down to hold water in. When it warps, hardens, or gets a mineral crust on its edge, water trickles past it into the bowl. This is the number one cause of a running toilet, and it accounts for roughly 70 percent of the calls we run.
Test it in ten seconds: shut the water off at the wall valve, flush the toilet, and watch the tank. If the water level drops on its own, the flapper is leaking. If it holds, the problem is up top with the fill valve or float.
The fill valve
The fill valve is the tall plastic tower on the left side of the tank. It refills the tank after every flush and shuts off when the float reaches the set level. When the internal diaphragm wears out, the valve never fully closes. You will hear a constant high-pitched hiss even when the tank is full.
Fill valves in Suffolk typically last 8 to 12 years. If yours is original to a house built in the 2000s, it is on borrowed time.
The float
The float is the ball or cup that rides on the water and tells the fill valve when to stop. On older toilets it is a brass arm with a plastic or copper ball at the end. On newer ones it is a plastic cup that slides up and down the fill valve shaft. A float that has cracked, filled with water, or slipped out of adjustment will keep the valve open.
The overflow tube and refill tube
The overflow tube is the open-ended pipe in the center of the tank. If the water level is set too high, water spills into the overflow and down the drain continuously. The refill tube, the thin hose clipped to the top of the overflow, should point down into the tube, not sit submerged in the tank water. A refill tube pushed too far down will siphon water out of the tank all night.
How to fix a running toilet in Suffolk: step by step
Fixing a running toilet in Suffolk is a 30 to 60 minute job for most homeowners with basic tools. You need an adjustable wrench, a sponge, a small bucket, and the replacement part. Turn the water off at the wall valve behind the toilet before you start, and flush once to empty the tank.
- Identify the failing part. Use the ten-second flapper test above. If the tank drains on its own, replace the flapper. If it holds but the valve keeps hissing, replace the fill valve.
- Shut off the water and drain the tank. Turn the wall valve clockwise until it stops. Flush. Sponge out the last inch of water so you are not working blind.
- Replace the flapper. Unhook the old flapper from the two tabs on the overflow tube and the chain from the handle arm. Take it to the store with you so you match the size. Install the new one, hook the chain with about half an inch of slack, and turn the water back on.
- Replace the fill valve. If you are going this route, buy a complete fill valve kit. Shut the water off, drain the tank, disconnect the supply line at the bottom, unscrew the lock nut under the tank, and lift the old valve out. Drop the new one in, tighten the nut hand-tight plus a quarter turn, reconnect the supply, and adjust the float so the water sits about one inch below the top of the overflow tube.
- Check the refill tube. It should clip to the top of the overflow and point down into it, ending about a quarter inch above the water line. If it is jammed down inside the overflow, pull it up.
- Test. Turn the water on, let the tank fill, and listen. No hiss, no trickle, no refill cycle after 20 minutes means you are done.
If you would rather not spend a Saturday on your knees behind a toilet, our team handles toilet repair Suffolk VA same-day in most cases. We carry the common flappers and fill valves on the truck, so it is usually a one-visit job.
If the toilet itself is 20-plus years old and you have already replaced the flapper twice this year, replacement often makes more sense than another repair. A modern 1.28 gallon-per-flush toilet will cut your water use by roughly 20 percent compared to a 1990s 1.6 gpf model, and we handle toilet replacement Suffolk VA with haul-away of the old unit included.
What a running toilet costs to fix in Suffolk, Virginia
Typical 2026 pricing in this area runs $15 to $40 for the part and $125 to $225 for a service call that includes the repair. A flapper-only fix is at the low end. A full fill valve replacement with a new supply line sits at the high end.
Here is how the numbers break down for the most common jobs:
- Flapper replacement: $15-$25 part, $125-$165 total with labor.
- Fill valve replacement: $20-$40 part, $150-$200 total with labor.
- Flapper and fill valve together: $175-$225 total. This is what we end up doing on about a third of the toilets we see, because if one rubber part has failed the other is usually close behind.
- Flush valve seat replacement (if the seat itself is pitted): $200-$275, since the tank has to come off.
- Full toilet replacement: $350-$700 installed, depending on the model and whether the flange needs work.
If the running toilet is one of several problems in an older home, it is worth having us look at the whole system while we are there. We regularly find running toilets sitting next to a failing supply line or a corroded shutoff valve, and fixing both at once costs far less than two separate visits.
Can a running toilet increase my water bill in Suffolk VA?
Yes, and the increase is bigger than most people expect. A toilet that runs constantly can waste 200 gallons a day or more. A slow flapper leak that only trickles can still waste 30 to 50 gallons a day.
Run the math on Suffolk water rates. At roughly $4 to $6 per 1,000 gallons for combined water and sewer, a 200-gallon-per-day leak adds about $25 to $35 a month to your bill. Over a year, that is $300 to $420 down the drain. The repair pays for itself in under two months.
You can check for a hidden leak without pulling the tank lid. Read your water meter at the curb, wait two hours without using any water in the house, and read it again. If the number moved, something is leaking. Nine times out of ten on a call like this, it is a toilet.
If the meter test points somewhere other than a toilet, our team runs leak detection Suffolk VA with acoustic and thermal equipment to find the source without tearing up walls or floors.
Common mistakes we see on DIY toilet repairs
We get called to fix a lot of half-finished toilet repairs, and the same handful of mistakes comes up over and over. Avoid these and your repair will hold.
- Not cleaning the flush valve seat. If you drop a new flapper onto a seat with mineral crust, it will leak within weeks. Scrub the seat with a nylon pad and rinse before installing.
- Cutting the flapper chain too short. A chain with no slack holds the flapper slightly open. Leave about half an inch of play.
- Over-tightening the fill valve lock nut. Hand-tight plus a quarter turn is enough. Crank it down and you will crack the tank or crush the gasket, and then you have a leak on the floor.
- Setting the water level too high. The water line should sit about one inch below the top of the overflow tube. Higher than that and the tank constantly spills into the overflow.
- Reusing the old supply line. A $6 braided supply line is cheap insurance. If yours is more than 10 years old, replace it while you have the tank drained.
- Ignoring a wobbling toilet. If the toilet rocks when you sit on it, the wax ring is likely failing. That is a separate repair and worth doing at the same time.
One more thing worth knowing: if your running toilet is in a bathroom that also has a slow drain or a gurgling sink, the two problems may be connected. A blocked vent stack can cause both. We handle drain cleaning Suffolk VA for exactly that kind of combined issue.
When to call a professional
Call a professional if the tank itself is cracked, if water is pooling on the floor around the base, if the shutoff valve behind the toilet will not close, or if you have replaced the flapper and fill valve and the toilet still runs. Those four situations are past the DIY stage.
Also call us if the toilet is in a rental property, if it is a one-piece or pressure-assisted model with parts you cannot source locally, or if you simply do not want to spend your weekend on it. Suffolk Plumbing Drain and Water Heaters handles running toilet repair across Suffolk and the surrounding towns, and we quote the price before we start so there are no surprises on the invoice.
Homeowners in the older neighborhoods around downtown and the historic district deal with a lot of original 1950s and 1960s plumbing, and running toilets there often come paired with worn shutoff valves and aging supply lines. If you are in one of those homes, it is worth having us look at the whole bathroom while we are on site. We also serve the surrounding communities, including Plumbing in Franklin and the outlying areas of Isle of Wight and Southampton counties.
Frequently Asked Questions
Why is my toilet running constantly in Suffolk VA?
It is almost always a worn flapper letting water escape the tank, which forces the fill valve to cycle every few minutes. A failing fill valve or a float set too high causes the same symptom. Suffolk's slightly hard water wears rubber parts faster than the manufacturer's estimate.
How do I fix a running toilet in Suffolk?
Shut the water off at the wall valve, drain the tank, and test the flapper by watching whether the water level drops on its own. If it does, replace the flapper. If it holds but the valve hisses, replace the fill valve. Most fixes take 30 to 60 minutes.
How much does it cost to fix a running toilet in Suffolk, Virginia?
In 2026, expect $125 to $225 for a professional repair, including the part. A flapper-only job runs $125 to $165. A fill valve replacement runs $150 to $200. DIY parts cost $15 to $40 at any local hardware store.
Can a running toilet increase my water bill in Suffolk VA?
Yes. A constantly running toilet can waste 200 gallons a day, which adds roughly $25 to $35 a month at Suffolk water and sewer rates. Even a slow flapper leak wastes 30 to 50 gallons daily. The repair usually pays for itself in under two months.
Should I call a plumber for a running toilet in Suffolk VA?
Call a plumber if the tank is cracked, water is pooling on the floor, the shutoff valve will not close, or a flapper and fill valve replacement did not stop the running. Otherwise, a flapper swap is a reasonable DIY job for most homeowners.
Get help with Plumbing in Suffolk
If your toilet has been running for more than a day, the water waste is real money and the fix is usually quick. We diagnose it, quote the price, and have it quiet again the same visit.
Call Suffolk Plumbing Drain and Water Heaters at (757) 829-9304 to schedule running toilet repair in Suffolk and the surrounding areas.
