How to Find and Replace a Toilet Tank

Whether it’s because of damage, or an unusual creative whim, it sometimes becomes necessary to be in need of a toilet tank replacement. Fortunately, this probably isn’t as hard, or expensive as you may think.

In this article, you will learn about how to identify what kind of toilet tank fits your toilet, and how to go about finding and replacing the tank.

Common Tank Problems That Could Warrant a Replacement

Some issues may appear to mean the tank is broken. However, they can be fixed without a replacement.

The Toilet is Randomly Flushing

If your toilet is flushing on its own, the toilet tank is probably leaking water into the toilet. Because this empties the tank, it will initiate a flush and refill itself. While it may appear to be a problem with the tank itself, rather, it is a problem with a mechanism called a flapper. The flapper seals the tank and prevents water from unintentionally leaking into the bowl. Typically, cleaning the flapper is enough to fix the seal and resolve the issue. Other times, you may have to replace the flapper.

A Trickling Sound is Heard

If you hear a consistent trickling or hissing sound in the tank, it may not be a tank problem. This is surprising because the sound will appear to be coming right from the tank. This problem is often stemming from the other internals, such as the inlet valve, refill tube, or ballcock.

Do I have to Replace the Whole Toilet?

If you have determined that you need to replace the tank, don’t worry, you probably won’t need to replace the entire toilet. For modern and common toilets, the tank is usually less than the cost of a new whole toilet. However, if your toilet is older, it might actually be easier to buy a new toilet.

Toilets manufactured before 1994 likely do not fit today’s water efficiency standards, so finding a replacement will be incredibly difficult. Additionally, toilets made before 2000 tend to have piping more prone to clogging. Because of these changes over the years, you might find it easiest and most cost-effective to replace the entire unit.

Keep in mind that many toilets come in one-piece models, while others are two-piece. If your toilet is a one-piece, then you will need to replace the whole toilet. If it is a two-piece model, then you can individually replace the tank.

Types of Toilets

Before you can replace your toilet tank, you must know what type of toilet you have. The three primary types of toilets that may be in your home are:

Gravity Toilet

  • Most common in modern homes
  • Flushing mechanism uses gravity to move water from the bowl.

Pressure Assisted Toilet

  • Mechanism in the tank pushes water, rather than relying solely on gravity.
  • Pressure assisted toilets are more efficient at flushing and are less likely to clog.
  • Tanks for this style are going to be a little bit more expensive than gravity toilets

Dual Flush Toilet

  • Two buttons on top of the tank control how much water is used. This toilet style has two different options for flushing.
  • If your current toilet has two flushing options, you will want to make sure you have a tank that is compatible with dual flush toilets.
  • Dual flush toilet tanks will usually be the most expensive of these three main types.

Wall-Mount Toilets

Some homes have wall-mounted toilets instead of the more common floor-mounted toilets. Wall-mounted toilets store their tank inside of the wall. These toilets can still fall under the three categories listed above, they just hold their mechanisms in the wall.

Expect a tank for a wall-mounted toilet to be more expensive and a bit more complicated to install. However, it is still possible for the homeowner to complete a replacement on their own, without an expert plumber.

Because the gravity toilet is the closest to an industry-standard, gravity toilets have the most options for replacement tanks. You are most likely to easily interchange tanks on this particular style of toilet.

How to Find What Kind of Toilet You Have

Finding the Brand and Toilet Model

The first information you need is the brand name and the serial number of your toilet.

The brand can often be seen easily on the bowl itself near the back of the seat, or near the bottom of the bowl.

However, finding the brand name will often be a moot point, as the serial number will usually tell you everything you need to know with a simple Google search. The serial number is usually on the inside of the tank. It will be imprinted with a series of numbers and specifications.

Once you know the specific toilet tank model and brand, simply look up the number to see what model it is on the manufacturer’s site. There, you’ll be able to know more specifications. Some websites will also list replacement parts for sale.

Tanking Measurements of the Tank

While not necessary for all models, you might feel more comfortable taking measurements. You can use these measurements to double-check the sizes when you go to buy the replacement tank. You can take these measurements with just a piece of paper, a pen, and a tape measure.

Measurements to take:

  • Tank depth
  • Tank Length
  • Tank Width

You may want to know the pipe and fixture measurements as well. If you decide to choose a tank that is much different from your current one in shape, there is a small change you will need to also replace the piping. For this reason, it is recommended that you try to find a tank as similar to your current one as possible.

Bolt Sizes

Bolt sizes often vary between brands and models of tanks. The most common sizes are 1/4th inch and 5/16th inch, but it would be wise to double-check your bolts.

If you have a custom toilet or a toilet from a rarer brand, then your bolts could be different sizes.

If they are not eroded, the bolts should have the measurements written on them. Otherwise, you can take the measurement yourself. The bolts will be the same size as the holes.

Additionally, make sure the tank and your toilet bowl have the same number of attachment bolt holes. Some models have three and some models have two. You may want to pick up fresh bolts, nuts, and washers at the hardware store.

You will need the same amount as the number of attachment holes in your toilet. For example, if your current bowl is connected by three bolts, you will want three fresh bolts and accompanying washers. You will also need to make sure the bolts are the same size as the ones you currently are using.

Other Factors to Consider

While most toilets are pretty simple, some toilets have unique and custom features. You may want to double-check and make sure you know all features of your toilet before selecting a replacement tank.

  • Is your toilet wall-mounted?
  • Is your current tank recyclable?
  • Does the tank look good with your bowl?
  • Will the new tank look out of place in your bathroom?
  • Do you want to install the toilet or have a professional plumber do it? Plumbing services can be several hundred dollars, so doing it yourself saves a great deal of money.
  • What is your toilet made of? Most toilets are made of vitreous china, however, cheaper toilets may be made of plastic. It is recommended to use the same material for the bowl and the tank to ensure no weighting problems.

Common Toilet Brands

Toilets are designed to have a certain shape of the tank for purely aesthetic purposes, as well.

If you have a tank from a different brand than your bowl, you may find that your bathroom décor is less appealing because your toilet tank stylistically sticks out like a sore thumb. For this reason, you may want to make sure the brand and series of the toilet tank is the same as the bowl.

When searching for a new toilet tank that is universal to what you already have, you will probably run across these varieties:

  • TOTO
  • American Standard
  • Sterling
  • Glacier Bay
  • AquaSource
  • Kohler

It is easiest to find replacement parts from the company that manufactures your toilet bowl. Many companies have products that are interchangeable to a degree, especially the most popular brands. They often have universal tanks that you can choose from. It is recommended to check their website for specifications on your current toilet when checking for replacement parts.

Will the Tank be Expensive to Replace?

The costs associated with replacing a tank vary by model and if you plan to install it yourself. If you choose to hire a plumber for installation, then the cost will be higher.

For modern toilets, the cost of the tank itself is usually cheaper than replacing the whole toilet. Typical tank prices are less than half of the full toilet cost. However, not all toilets will have compatible parts available.

As mentioned previously, wall-mounted toilets and floor-mounted toilets come at different price points. You can expect to pay more for a wall-mounted tank.

Where to Buy the Replacement Tank

Hardware or Home Improvement Store

Once you have written down all the above information about your toilet, go to a local hardware or home improvement store. With these specifications, a store employee can direct you to the correct model. If they do not have the exact model of your toilet, the store expert can show you which other brands are compatible with your specifications.

Remember, toilet tanks can get heavy. These days, most stores offer services such as home delivery or store pick-up. If you are concerned about the weight of the toilet tank, it is a good idea to ask about getting assistance with lifting your tank out of the store.

Manufacturer Website

You can also find your model of the toilet on the manufacturer’s website. Simply google the model and brand number of your toilet. Many brands will have parts for sale. They may also direct you to official retailers that will sell the parts.

If you buy online, you can have your toilet tank shipped to you.

Outlets, Salvage Yards, and More

If you have an older toilet, you might not be able to find suitable tanks at your local store. Furthermore, typical retailers may not carry these older models anymore. Older tanks may be found at salvage yards and outlets that sell old stock from retailers.

How to Replace the Tank Yourself

To go the DIY route, you need a few tools to be able to get the job done. Some of this you likely already have in a closet or garage. Others you may have to get from a hardware store or plumbing supply outlet if they didn’t come with the toilet that you bought.

Materials Needed

  • New Tank
  • Screwdriver
  • Wrench
  • Towels
  • Rubber gasket (likely comes with your tank)
  • Rubber and metal washers (same number as attachment holes on your tank)
  • Bolts (same number as attachment holes on your tank)

Steps to Replace the Tank

1. Use the water valve to cut off the water supply to the toilet. The water valve is located on the wall, connected to the tank by a tube or pipe. To turn the water off, turn the valve counterclockwise.

2. Flush the toilet to drain all water from both the tank and the bowl. There will probably be some leftover drops of water in the bottom corners of the tank. Use a sponge or towel to dry up leftover water. Wiping up this water prevents spills. If the tank starts to refill, it means the water valve was not twisted enough to fully cut off the water supply.

3. Disconnect supply hose from the tank. The supply hose is the part that connects the water valve and the tank.

4. Remove the toilet tank lid.

5. Loosen bolts that attach the tank and bowl. Tanks typically have two or three bolts that attach them to the bowl.

6. Remove the toilet tank (be careful, it may be heavy!)

7. Set the new tank in the same position as the old tank, lining up the mounting holes with those in the bowl. Your tank may come with a rubber gasket that goes onto the bottom of the tank. If not, one can be bought at the hardware store.

8. From inside the tank, put a rubber washer over each mounting bolt.

9. From behind the bowl, put a metal washer on each bolt and turn the nuts onto the bolts.

10. Tighten the nuts from inside the toilet.

11. Reconnect the hose to the new tank.

12. Turn the water supply back on with the water valve. Then, just flush the toilet to test for leaks.


If your toilet tank is broken, you can use your model number and brand to find a replacement tank online or at your local hardware store. Make sure the new tank is the same flushing style as your current toilet.

Once you have the right tank, you can either install it yourself or call a plumber. Installing a tank can be tricky, so there is no shame to be had in seeking an expert. Once the correct tank is installed and tested, your toilet tank change has been completed!


Leave a Comment