1.28 GPF VS 1.6 GPF Toilets: Which One to Choose?

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Buying a new toilet may seem like a fairly simple decision initially. However, there are a few factors that you need to consider before heading out to the store, especially if you live in a drought-prone state. 

Today, the flush power of a toilet is more important than ever. High efficiency or low-flow toilets have a 1.6 to 1.28 GPF (Gallons per Flush) or lower, though these two are the most common types. 

So when it comes to 1.28 vs 1.6 GPF toilets, which is better? Ultimately it comes down to whether it’s more important for you to have a toilet with a greater flush power or one that can save water at a higher rate.

Having managed residential properties for several years, I’ve definitely had my share of toilet and plumbing issues. 

And if it’s one thing that I know for sure, the amount of flash power that your toilet has will definitely impact your water bill and the overall condition of your home’s plumbing system, especially if you have more than one toilet or a large household.

A Background on the Low Flow Toilet

Energy-efficient toilets were introduced in 1994 per the Energy Policy Act. Why? Because the United States government wanted to enact a policy that would help preserve water in the country, especially in states that tend to be drought-prone, such as those located in western and southern regions. 

Before these toilets came into existence, your average toilet used anywhere from 3 to 7 gallons for one flush. Keep in mind that your average person uses the bathroom about 4 to 7 times a day. 

So doing the numbers, it means that people used a whopping 49 gallons or more of water just to flush the toilet– and that’s just for one person!

To save water at a higher rate, toilet manufacturers pretty much went back to the drawing board to design toilets that would require less water utilization per flush. As a result, water-efficient toilets hit the marketplace to offer around a 70% reduction in water usage.

1.6 GPF Toilet Restrictions  

In addition to federal regulations, some state governments have also created laws to limit the maximum water usage for toilets. 

Most notably, the states of California, Texas, Georgia, and Colorado have included new low flush efficiency standards in their building codes stating that any toilets sold in their states cannot use more than 1.28 gallons per flush. This pretty much put the ax down on 1.6 GPF toilets.

1.28 GPF VS 1.6 GPF Toilets

Though the main difference between 1.28 GPF and 1.6 GPF toilets is the amount of water needed to flush the toilet, there are other noticeable differences that come into play when comparing these types of toilets. 

And if you’re in the market for a new toilet, it helps to know more about these differences so that you can determine which one will be more beneficial for your home.

Flush Power

The main difference between the two types is the flush power. Though both toilets use less water than their predecessors, 1.6 GPF toilets have a slightly higher flush power than the 1.28 GPF toilet. 

Also, 1.6 GPF toilets have a larger flush valve, which allows more water to enter the toilet bowl, translating to a stronger and more powerful flush.

Why is this important? Well, because a stronger flush power means the toilet will be less likely to clog. 

This means that in scenarios where you may accidentally flush too much toilet paper, or flush non-biodegradable items, or have a large amount of waste to flush, a 1.6 GPF toilet will be better equipped at providing a flush powerful enough. 

Not only does it cut down on the number of times you have to flush the toilet, but it can potentially reduce the number of times you’ll need to break out the old plunger–which is never a fun time. 

Water Efficiency

As you can probably guess by now, a 1.28 GPF toilet does save a bit more water per flush than a 1.6 GPF toilet. So if you have a larger household or want to save as much as possible on your water bill, you may lean towards the 1.28 toilet. 

On average it uses about 20-25% less water per flush. So, let’s say for example you have 3 people living in your home and everyone flushes the toilet 6 times a day on average. 

With a 1.2 GPF toilet, your total water expenditure during a 30-day period will come to 192 gallons. With 1.6 GPF toilets, your total water expenditure during the same time period would come to 240 gallons. 

Note that this is just for toilet usage; it doesn’t include water for showers and faucets throughout the home. To get an idea of what this translates to, take a look at your water bill to examine your local water usage charges (per gallon) and your average monthly water consumption. 

Doing so can give you a closer idea of what you can save month-to-month.

Cost Factor

Is cost your main concern? This may surprise you but the average 1.28 GPF toilet is typically more expensive than 1.6 GPF toilets and by anywhere from 10-20%. Why? Because it simply saves more water and is, therefore, more efficient. 

Not only that, but some states also offer a rebate when you purchase the 1.28 GPF toilet, as it helps them keep down water usage within the state. You can find more information about these rebates on your local state government site or the WaterSense page on the EPA’s website. 

In this category, the 1.28 GPF may still be the winner, at least when you consider long-term savings. Upfront, the toilet may cost a bit more, but you’ll get the return in your water savings over the next few months. So here the 1.28 gains another point in the 1.28 vs 1.6 GPF battle.


So let’s discuss maintenance. I think it’s ok to say that most people don’t enjoy actually cleaning a toilet. And the extent to which you loathe this particular chore may play a part in your toilet buying process. 

If you purchase a 1.28 GPF toilet, you may find yourself dealing with toilets clogged more often due to their weaker flushing capability (though some toilet brands are better than others). You’ll find this issue is less common with 1.6 GPF toilets. 

Again, this comes back to the power of the flush. So if you’re prone to clogs or leaving marks in the toilet after dropping off a few friends, you may want to consider 1.6 GPF toilets to minimize the amount of day-to-day cleaning and maintenance that you may have to do. 

And remember that sometimes a simple plunging of the toilet may not do the trick, particularly when you’ve flushed non-biodegradable materials down the toilet such as feminine hygiene products, baby wipes, and other items. 

That being stated, it’s also important to consider potential plumbing costs that you may incur in the event that you have to hire a licensed plumber to remove a clog in your toilet


Do you prefer the most environmentally friendly option? If so, then the 1.28 GPF toilet is likely the best option for you. The pressure to minimize the strain on natural resources such as water often equates to local and federal governments initiating mandates to help protect the environment. 

And believe it or not, you can play a small part in this by simply purchasing a low-flow toilet. Yes, believe it or not, altruism even has a place within the toilet selection process. When comparing the 1.28 vs 1.6 GPF in terms of eco-friendliness, the 1.28 will always win.

Best 1.6 GPF Toilet

There are quite a number of different options for 1.6GPF toilets, but for this post, we picked our favorite for anyone not living in Colorado, California, Texas, and Georgia.

TOTO Drake 2-Piece Ada Toilet with Elongated Bowl

1.28 GPF VS 1.6 GPF Toilets: Which One to Choose? 11.28 GPF VS 1.6 GPF Toilets: Which One to Choose? 2


  • Offers a strong yet quiet flush
  • Is ADA Compliant
  • Has an elongated seat to fit body types
  • Easy to clean
  • Flushes quickly
  • Doesn’t clog easily


  • Can’t be purchased in certain states
  • Less eco-friendly than 1.28 toilet options

The 2-piece Drake toilet by TOTO is one of the best options on the market when it comes to providing a clog-free flush that is as powerful as it is fast. And to top it off, the toilet’s flush is fairly quiet considering its commercial-grade flushing power.

It also has a contemporary two-piece design with a high-profile tank for easy access.

The toilet comes with a standard one-year warranty and offers a great combination of low water usage and a powerful flush. It’s ADA compliant and includes a 3-inch flush valve which is over 100% larger than your typical 2-inch flush valve. 

If you’re looking for 1.6 GPF toilets that are low maintenance and have a dampened flushing mechanism, here’s a good model to consider.

Best 1.28GPF Toilet 

If you prefer to save as much water as possible or live in a state that has restrictions to 1.28GPF toilets only, here are a few options that are worth considering.

TOTO Eco Ultramax ADA Elongated One Piece Toilet 1.28GPF

1.28 GPF VS 1.6 GPF Toilets: Which One to Choose? 31.28 GPF VS 1.6 GPF Toilets: Which One to Choose? 4


  • Comfortable height for various body sizes
  • Has a sleek and stylish design
  • Easy to clean
  • Eco-friendly
  • Minimizes water consumption


  • It’s expensive
  • You may need to flush more than once
  • The bowl is shallow

Here is another toilet by the renowned TOTO toilet brand. This elongated one-piece low flush toilet offers a soft-close seat, so you don’t have to worry about the jarring sound of a lid slamming in the middle of night. 

The toilet stands 27 1/2 inches tall, which is a fairly comfortable height and it’s also ADA approved. In addition to this, the 1.28 toilet is also CEC, WaterSense, and Calgreen compliant. 

It’s made with a trademark ceramic glaze to prevent scale, iron, and mold from sticking to the surface of the toilet tank and bowl. So if you want a low-maintenance toilet that’s easy to clean, here’s one to consider. 

This toilet has a sleek profile, which is fitting to its one-piece design and it includes a 2-inch flush valve for maximum efficiency. It ranks in the top 5 in terms of the best high efficiency toilets. 

1.28 and 1.6 GPF Toilets Alternative

Sometimes you want to have your cake and eat it too. And if you’re wondering how to get the best of both worlds with a toilet that can save water but that also has sufficient pushing power, you’re not alone. 

And more importantly, there is an option available. It’s called a dual flush toilet. These versatile low flush toilets are making their presence known in the industry as they offer both 1.28 and 1.6 GPF flushing options. 

This means that you can simply use the lighter flush option for liquid waste and the heavy flush for solid waste (there is a big and a small flush button on top of the toilet). 

And the great thing is that most dual flush toilets are also WaterSense certified. 

So if you live in a state, such as Texas or Colorado, you can definitely purchase one of these dual flush toilets and be compliant with your local state codes. Check out this link to learn more about dual flush toilets.


So who wins in the 1.28 vs 1.6 GPF battle? Overall, I’d have to say that I personally prefer the 1.6 GPF toilet. The less time I have to spend around the toilet, the better. 

And in my opinion, any initial cost differences or yearly savings are offset by my simple desire to go with the option that offers me the most convenience on a day-to-day basis. 

If you have a larger household, you’re likely going to want to save more water than someone who lives alone, so a 1.28 may be a better option. 

However, if flushing power is of the utmost importance to you and you don’t consume a lot of water on a regular basis, the 1.6 may be a better fit. And of course, if you’re completely undecided, there’s always the dual-flush option as well.

Once you’ve figured out which toilet works best for your household, compare prices online or at your local home appliance store to find your new toilet!

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