13A vs 32A hot tubs – what it means and which suits your home
Thinking about getting a hot tub? New or second-hand, it’s exciting… right up until someone mentions electrics. 13A. 32A. Hard-wired. Plug and play. If you’re sat there thinking “Okay, but what does that actually mean?”, you’re not alone.
Let’s break down 13A vs 32A hot tubs in plain English, so you can choose the right setup for your home, your budget, and how you’ll really use the tub.
The quick definition (because we all want one)
A 13A hot tub plugs into a standard UK socket, like a kettle or any other appliance does.
A 32A hot tub is connected to a dedicated electrical supply and is usually hard-wired by an electrician.
That’s the headline. Now let’s look at what that means in real life.
What does “A” mean anyway?
The “A” stands for amps, which is basically a measure of how much electrical current something can use.
A normal UK plug socket is designed for up to 13 amps. That’s why so many household appliances run happily on a plug.
A 32 amp supply gives a hot tub far more power to play with, but it needs a proper setup to do it safely.
13A hot tubs – the plug-in option
A 13A hot tub is all about convenience.
Why people like 13A hot tubs
- You can often get it running without electrical work straight away
- It’s a simpler option for many homes
- It can suit lighter, occasional use
If you’re buying a second-hand hot tub and you want to test it before spending more money, 13A can feel like the safe bet.
The trade-offs with 13A
Here’s the thing. A hot tub is not a tiny device. It’s heating a big volume of water and running pumps at the same time. With 13 amps, the tub has to manage what it can run at once.
So you may notice:
- The heater pauses when the jets are on full power
- The water temperature can dip during longer sessions
- Heating takes longer, especially in colder months
That doesn’t mean something’s wrong. It’s simply the limitation of a plug supply.
32A hot tubs – the dedicated supply
A 32A hot tub is designed to run more like you’d expect a hot tub to run. Strong jets, steady heat, fewer compromises.
Why 32A often feels “better”
With more power available, the tub can usually:
- Run the heater and pumps together
- Hold temperature during use
- Recover heat quicker afterwards
- Deliver consistent jet performance
If you picture a busy weekend with friends, or you want to use the tub year-round, 32A tends to suit that lifestyle.
What a 32A setup usually involves
In a typical UK installation, a 32A supply will include:
- A dedicated circuit from the consumer unit
- Correct cabling
- RCD protection
- An external rotary isolator
This is electrician territory. It’s not a DIY job.
Running costs… does 32A cost more?
This question comes up a lot, and the answer is “it depends”.
A 32A hot tub does not automatically cost more to run just because it has a bigger supply. The supply is about capacity, not constant usage.
What affects running cost more is:
- Insulation quality (tub and cover)
- How often you use it
- Set temperature
- Outdoor temperature and wind exposure
- How long the cover stays open
- Water care and filtration health
In practice, a 32A hot tub can be more efficient in certain situations because it can maintain temperature more effectively during use, rather than dropping and then spending ages reheating.
Which is better for a new hot tub?
Many new hot tubs, especially mid-range and premium models, are designed with a 32A supply in mind.
Some are configurable and can run on 13A initially, then be upgraded later. Others are 32A only.
If you’re buying new, check:
- The manual or product spec
- Whether it’s 13A only, 32A only, or convertible
And if you’re not sure, ask before you buy. It can save a headache later.
Which is better for a second-hand hot tub?
Second-hand is where people get caught out, because what you see is not always what you’re getting.
A hot tub might have a standard plug on it and still not be “truly” designed for 13A long-term. Sometimes tubs are adapted so they can run off a plug, but performance is not the same.
Quick clues (not a substitute for checking properly)
- A standard plug suggests 13A operation
- A thick armoured cable suggests a 32A setup
- If the heater stops when jets are on, it may be running in 13A mode
Still, tubs vary massively. A proper inspection is the safest way to confirm what’s required.
Access and positioning can affect your decision
This might sound like a tangent, but it matters. Where the hot tub sits affects cable routes, isolator placement, and the practicality of the supply.
If the only sensible location is far from the house, a 32A installation may need a longer cable run and more planning.
And if you’re buying a second-hand hot tub that needs moving into place, it’s worth thinking ahead. Speaking to professional hot tub movers early can help you avoid buying something that won’t fit through the access or won’t suit your setup once it’s in the garden.
So… which should you choose?
Let’s keep it simple.
Choose 13A if:
- You want the simplest setup to get started
- You’ll use the tub occasionally
- You’re happy with slower heating and some compromises
- You’re testing a second-hand tub before investing further
Choose 32A if:
- You want strong, consistent performance
- You’ll use it regularly or year-round
- You don’t want the heater cutting out when the jets are on
- You’re investing in a higher-spec tub
A word on safety (because it’s worth saying)
Hot tubs mix electricity and water, so safety is non-negotiable.
For any permanent outdoor supply, especially 32A setups, use a qualified electrician and follow manufacturer guidance. If you’re ever unsure, pause and get it checked. It’s not worth guessing.
13A vs 32A hot tubs – choosing the right one for you
The difference between 13A and 32A hot tubs comes down to how much power your tub can use, and what that allows it to do day to day.
13A is often simpler to start with and can suit lighter use.
32A tends to deliver the full hot tub experience, with fewer compromises.
Work out how you want to use the tub, check the spec before you buy, and plan your electrics early. That’s what keeps it all stress-free, whether you’re buying new, buying second-hand, or arranging a move into position.
Frequently Asked Questions...
Can you run a 32A hot tub on a 13A plug?
Some hot tubs can be configured to run on 13A, but not all. Even when it’s possible, performance can be limited because the heater may pause when the jets are running. Always check the manufacturer spec or manual for your exact model.
Does a 32A hot tub cost more to run than a 13A hot tub?
Not automatically. The supply (13A or 32A) is about capacity, not constant usage. Running costs depend more on insulation, cover quality, outdoor temperature, how often you use it, and how long the cover is left open.
What’s better for a second-hand hot tub, 13A or 32A?
It depends on the model and how you’ll use it. 13A can be a simple way to get started, especially for occasional use. 32A usually suits regular, year-round use because it can maintain temperature while the jets are running.
How do we know if our hot tub is 13A or 32A?
A standard UK plug usually suggests 13A operation, while a hard-wired connection and isolator typically indicates 32A. Some tubs can be switched between modes, so the safest approach is to check the label, manual, or control pack details.
Do we need an electrician for a 32A hot tub?
Yes. A 32A hot tub needs a dedicated supply and should be installed by a qualified electrician, following the manufacturer’s requirements. It’s not something to DIY.
