How Much Water Does a Toilet Use?

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Considering that almost a quarter of a person’s daily water usage goes for flushing the toilet, knowing how much water a toilet uses can help us to conserve water and save money in the process.
Let’s take a look at the stats of toilet water usage and ways to reduce unnecessary water wastage (no pun intended) in the toilet.

What the Numbers Say
- Flushing toilets is the single highest use of water in the average home
- Flushing uses up to 24% of a person’s total daily water usage
- Toilets from the 80s and before use up to 7 gallons per flush (gpf)
- After 1994, federal mandates limited toilets to a maximum of 1.6 gallons per flush
- The average person flushes up around 5 – 8 times a day
- WaterSense certified toilets use as little as 1.28 gallons of water per flush
- Dual flush toilets use between 1.1 gpf to 1.4 gpf depending on if its half or full flush
By switching to a more efficient toilet, you’ll be able to save water and money. Here’s how the numbers break down.
Let’s say you’re still using a pre-1994 toilet in an older home. Here’s how the savings would compare if you switched to a 1.6 gpf or 1.28 gpf model.
- 3.5 (gallons per flush of toilet) x 5 (number of times a person uses the toilet per day) x 365 days per year = 6,387.5 gallons per year for flushing
- 1.6 gpf x 5 x 365 = 2,920 gallons per year for flushing
- 1.28 x 5 x 365 = 2,336
By changing your old toilet to a standard modern toilet, you can save up to 4000 gallons of water per year. If you’re switching from a modern toilet to a highly efficient model, you can save up to 584 gallons per year.
How to Save Water When Flushing

If most of our daily water usage goes for flushing toilets, this means that addressing this can result in significant water savings. Here are some ways to ensure that you’re making the most out of every gallon going down the toilet drain.
- Get a high-efficiency toilet:
As we’ve already outlined, simply switching to a low flow toilet can save hundreds of gallons of water per year. These toilets are designed to be as efficient as higher flow toilets. In other words, low flow doesn’t mean you have to sacrifice on performance.
Look for the WaterSense certification when installing a new toilet, as these are certified to be water efficient yet equivalent to regular toilets in terms of performance. Some water suppliers offer incentives and rebates if you have WaterSense certified toilets installed at home.
- Install a dual flush toilet:
Dual flush toilets are a modern variation of low flow toilets. These work by offering the user options when it comes to flushing – a half flush (to flush liquids and paper) and a full flush (for solids and paper). These systems are highly efficient and reduces unnecessary wastage. Use the half flush option as much as possible when using a dual flush toilet.
- Put something large in the toilet tank:
If you don’t have the option of upgrading to a more efficient toilet, simply put in something heavy and large into your toilet water tank. Some good candidates include a brick or a full plastic bottle of water.
What this does is to reduce the amount of water that would fill up the tank, thereby reducing the amount of water for flushing overall. Most toilets have a line marking the point that the water fills up to. Ensure that the water doesn’t go above this line to prevent water wastage.
- Use a water saving device:
There are handy gadgets and devices that allow you to save water easily simply by installing them to your toilet system. We’ve covered them in detail in this article.
- Find and fix toilet leaks:
Toilet leaks are responsible for an obscene amount of water waste each year. A normal leak in the toilet can waste over 6000 gallons of water per month, costing you hundreds of dollars in utility bills. Some indications of a toilet leak include hearing the water filling the toilet tank incessantly or seeing puddles of water around the base of the toilet. Find and fix them as soon as they come, as that’s one easy way to save unnecessary water wastage.
The Bottom Line
Every day we flush gallons upon gallons of water into the toilet, but with a little awareness we can take steps to reduce unnecessary water usage and make the most of every gallon. This will not only save water but will also translate to saving money.