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What Size Wire for 50 Amp Hot Tub? (Quick Answers)

You may have noticed that most modern spas and homes have hot tubs as they are comfortable and quite luxurious. You may buy one for yourself if you plan on using it regularly. 

If you do not use a hot tub regularly, it will simply be a waste of energy and pose a threat to health if not properly maintained.

Wire size for 50 amp hot tub

Generally, 50-amp hot tubs require a 6-gauge copper wire. However, in some instances, users may have to use 8-gauge copper wires for safety reasons. 50-amp hot tubs can accommodate about 6 to 12 people. So, they require a significant amount of electric power and about 240 volts.

Commonly, you can see a 50-amp hot tub in most modern spas and some luxurious homes. They are spacious but take up a vast area and require regular maintenance. As a result, most people only decide to buy a 50-amp hot tub for themselves if they want to use it regularly.

Most 50-amp hot tubs require significant power to operate and need a 4-wires connection from the main circuit breaker panel. 

In some areas, you will have the option to install a ground-fault circuit interrupter (GFCI) for the hot tub, but in specific areas, you will have to install it. Also, a 50-amp hot tub uses about 220-240 volts so check that your wires can support this voltage rating.

For safety reasons, you should install a separate GFCI for your hot tub and ensure that it is within line of sight from the hot tub. As for the breaker, you can choose a 60-amp breaker or a 50-amp breaker to be more cautious. 

You may want to read the owner’s manual for the hot tub to understand which breaker rating will be best suitable.

One of the most crucial parts of a hot tub is the wire size. For a 50-amp hot tub that can accommodate about 6 to 12 people, it is advisable to use 6-gauge wiring. 

However, some manufacturers state that you can use an 8-gauge wire instead, but it is better to use a 6-gauge wire to stay on the safe side.

Few hot tub owners worry about which wire size to use for the ground and breaker wires. To answer this concern, you should use a 6-gauge wire. Certain manufacturers state you can use 8-gauge wire, but people advise using 6-gauge wires for safety reasons.

For additional safety, install every single wire in a tube. You can select the material of the conduit to be rigid, flexible, or PVC. Also, make sure a certified professional electrician does all the electrical work of the hot tub.

Can 8-gauge wire handle 50 amps hot tub?

Under normal circumstances, an 8-gauge wire cannot handle a 50-amp hot tub. By normal circumstances, we mean temperatures approximately that of room temperature, about 20-25°C or 68-77°F. So, experts recommend using 6-gauge wires for a 50-amp hot tub.

At room temperature, 8-gauge wires can handle a maximum of 40 amperes. Therefore, if you connect an 8-gauge wire to your hot tub to power it, the 50-amp current will significantly increase the temperature of the wire and force the insulation around the wire to melt. 

It will result in hazardous situations and electrical fire.

However, in a controlled environment, an 8-gauge wire can handle a 50-amp hot tub if the temperature is above 90°C or 194°F. But it is impossible to obtain these high temperatures in a home without causing any issues. 

So, refrain from using an 8-gauge wire to power your 50-amp hot tub, and use a 6-gauge wire instead.

What kind of wire for 50 amp hot tub?

According to experts, you should use an American Wire Gauge (AWG) 6 wire to power your hot tub. Depending on the hot tub model and manufacturer, you may be able to use an AWG 8 wire instead of an AWG 6 wire. 

Still, to stay safe from electrical hazards and fire, you should stick to using AWG 6 wires to power your 50-amp hot tub.

As mentioned earlier, a 50-amp hot tub pulls loads of power. Consequently, you must install the tubes for the wires to run through. For hot tub wiring, people generally use plastic and waterproof conduit to prevent water from storing around the wires and creating a hazard.

As for the conducting material, you can use either aluminum wires or copper wires. If you have not decided already which type you want to use, you can see the manual that comes with the hot tub. 

Please note that using aluminum cables instead of copper wires sometimes voids the warranty, so consult with the manufacturer beforehand.

How to calculate 50 amp hot tub wire size?

If you want to calculate the wire size for your 50-amp hot tub, follow the topics below. Please consider all the points listed to ensure you get the most suitable wire size.

NEC 80% Rule:

The National Electrical Code (NEC) 80% Rule means that the wire or circuitry chosen should have 20% on top of the required capacity. Therefore, to do the math of a 50-amp appliance, you will have to divide 50A by 0.8, which gives 62.5A. 

So, the chosen wire for your hot tub should support at least 62.5A. An AWG 6 wire supports up to 65A, making it appropriate for use in this scenario.


Most people are misinformed that different voltage ratings mean different wire sizes. While choosing a suitable wire, you should consider the supported wattage. To calculate wattage, you multiply the voltage rating with the amperes. 

In this case, it will be 50A into 220V, which gives 11,000W. An AWG 6 wire can support 11kW, making it the most suitable wire for the 50-amp hot tub. If your circuits have a voltage rating of 240V, you will multiply 50A with 240V and get the most suitable wire. 

It is likely it will be an AWG 6 wire.

Length of the wires:

Few people do not consider the wire length when installing a hot tub. The wire length determines the amount of voltage dropped over a distance. 

A quick way to determine the appropriate distance is by remembering that for every 100 feet, the voltage drops by 20%. Therefore, if you have to use a wire longer than 100 feet, you will have to use a thicker wire to make room for more amperes.

Bear these points in mind before deciding between wire sizes. Choosing an inappropriate wire can result in severe danger.

How do you wire a 50 amp hot tub?

You may have observed that a 50-amp hot tub has 4-wires. Follow the steps below to learn how you can wire your hot tub.

Make sure you have all the necessary tools:

Before starting, ensure you have all the tools you will require within reach. You will need a screwdriver, a breaker panel, and some wires.

Connect the wires in the appropriate slots:

The hot tub will have 4-wires. Two will be neutral and earthing, and the other two will be live. You will have to connect all the wires to their appropriate slots in the GFCI in the breaker panel.

You will see the slots are marked. The red and black wires are the live or hot wires, and the white wire is the neutral wire. The earthing wire is usually green.

After you have connected the hot tub wires to the breaker panel, you will have to use an extra wire to provide power to the breaker board. You will have to bring two live, one neutral, and one earthing wire from the main panel. Connect the wires accordingly to the GFCI.

Turn on the GFCI:

For a better-looking setup, you can mount the breaker panel of the hot tub on a wall. Also, make sure the wires are in a waterproof conduit. So water will not enter around the wires and cause interference.

When you have mounted the breaker panel, turn on the GFCI. Now you can safely enjoy using your hot tub.

Final Thoughts

Although a 50-amp hot tub is luxurious, setting one up can be difficult. But choosing the suitable wire size for your hot tub is simple, and you can do it yourself. For connecting the electrical wires, it is better to seek the help of a certified professional electrician to avoid complexities.