One of the important amenities on a boat is the toilet, known as a “head”. Everyone can use one at home, but marine toilets are very specific. So, what different types of toilet can you find on a boat? How do you flush it? What can or can’t you put down the toilet? How do you avoid spilling the contents of the tank, or sort out a clogged toilet? We’ll be answering these questions and more.

How to flush the toilet: mechanical versus electric toilets

Two main types of toilet can be found on a boat: mechanical or electric. Flushing an electric marine toilet is simple. You’ll usually find two buttons either marked “fill” or “drain”. At the touch of a button, you can effortlessly fill the bowl with water and flush it all away.

With a mechanical toilet, it’s a bit more involved and you’ll need to know more about how it works. Next to the toilet bowl there is a hand pump and then a switch to change between 2 processes (filling and draining). To use it, you’ll need to set the switch and then manually pump the handle up and down until the process is complete.

No matter whether it is electric or not, the method of using the on board toilet is as follows:

  1. Fill with the water.
  2. Do your business
  3. Pump out the water

If you’d prefer an electric toilet when sailing, we recommend renting the latest boat models. With boats from 2005 and older, you can usually forget about it having an electric toilet. The most luxurious yachts come with toilets that work on the vacuum principle (VacuFlush).


What you shouldn’t put down the onboard toilet

Some modern boats have an integrated shredder, with manufacturers claiming you can also put toilet paper down the toilet. However, we strongly advise against doing this. Many times we’ve seen some poor person having to take a clogged toilet apart to clean out the pipes. And it’s really not pleasant for anyone. So if you’re wondering where to dispose of used paper, we recommend buying smaller trash bags to place next to each toilet which you can then throw away regularly. Those of you who have ever spent a holiday in Greece will know all about this system.

So what shouldn’t you flush down a marine toilet?

  • Toilet paper
  • Pads or tampons
  • Wet wipes
  • Tissues
  • And we’d be very careful with food scraps.

Heeling and valves: beware of leaks

No valve in the world is 100 % leakproof. And that also goes for the valves on board. If you’re heeling too much, the contents of pipes, such as waste pipes, can spill out. Apart from being disgusting, large amounts of water can also damage the boat’s equipment, not to mention short-circuit the electrical wiring. So if you are expecting an exhilarating ride, close all the valves on board that could potentially cause a flood in the bathrooms. Valves are usually located under the floor near the bathroom, but inquire about their location when you check-in.

What to do if it won’t flush

When a toilet can’t be flushed, it is very unpleasant. There can be several reasons for this, so let’s look at them and do a bit of troubleshooting.

1) The valves are closed

This usually makes the hand pump very difficult to operate and feels like it’s springing back. Solution? Open the valves, but do nothing by force.

2) Too large or solid stools

In the long run, we would advise you to eat more fibre, fruits, vegetables and improve your drinking regime. However that won’t help with a clogged toilet. What may help is to try to soak the waste a little with warm water from the shower. This should help soften it so it can pass through the narrow pipes. If that doesn’t help, you can also just wait a bit of time for it to naturally break down a little.

3) The pipes are blocked

This is the worst-case scenario and means that the entire toilet system needs to be dismantled. On charter boats, you don’t often have any spare parts with you to do this competently, so it’s best to contact a mechanic somewhere in port. Expect to pay for this service.

What do you flush with?

Water, of course. But the question is really where the water comes from. On some boats this is from the sea, meaning it is in unlimited supply, whereas on others, it is water from the tank. In this case you’ll need to monitor how much you use. Find out about the whole process and method of flushing at check-in.

Use the marina whenever possible

Most marinas have toilets, showers and other sanitary facilities. When moored ashore, we recommend using them.

Over the railing, yes or no?

There is a big debate over this topic, mostly amongst men and sailors who race. It’s true that about 90 % of the male population will simply pee over the railing and not go down to the bathroom at all. However, there are skippers who consider such behavior to be a sign of disrespect for the boat and the marine life. We’ll leave it to you, to make up your own mind.