Hot Tub vs Hydrotherapy Pool: What’s the Difference?

Hot tubs and hydrotherapy pools are both popular wellness investments and are growing in popularity as a luxury feature in people's homes.  Whilst a hot tub and a hydrotherapy pool can look very similar and share some similar features, they actually serve different purposes.  In this blog we are going to explain the key differences between the two and help customers choose which type of spa is right for them.

What is a hot tub?

A hot tub is a large tub or small pool filled with heated water, designed primarily for relaxation, social enjoyment, and wellness. Most hot tubs are equipped with powerful jets that provide a massaging effect by circulating the water, helping to ease muscle tension and promote stress relief.

Here are the key features of a hot tub:

• Heated Water: Usually maintained at 37 - 40°C for comfort and relaxation and a few degrees warmer than a hydrotherapy pool. 
• Massage Jets: Provide a soothing massage effect for relaxation, often adjustable in intensity and direction. 
• Seating: Typically designed around built-in seats to accommodate multiple people in seated positions.
• Size: Usually on the smaller side and optimised for seating between 2–8 people. Hot tubs are usually smaller than pools as they are generally not designed for swimming or movement. 
• Purpose: Primarily used for relaxation, leisure, stress relief, recovery and social enjoyment.  

Unlike a hydrotherapy pool, which is designed with rehabilitation and therapeutic exercise in mind, a hot tub is generally more about pleasure, stress relief, and luxury lifestyle use.  Hot tubs are commonly featured in social spas, home residences and alongside swimming pools as a place to soak and relax.  

What is a hydrotherapy pool?

A hydrotherapy pool is a specially designed pool, used primarily for therapeutic purposes where warm water, buoyancy and water resistance are used to support rehabilitation and recovery.  

A hydrotherapy pool tends to be slightly larger than a hot tub to allow for movement in the water and will often contain features focused on rehabilitation such as hoists, ramps, targeted jet flows and other customisable water features.  

• Heated water:  Typically warmer than a standard swimming pool but cooler than a hot tub, averaging 33-36°C to relax muscles and improve circulation.  Some pools offer variable temperatures for hot and cold therapy. 
• Size and Depth:  Usually larger and deeper than a hot tub to allow a user to stand, stretch and do light exercise within the pool. 
• Jets:  Often targeted with variable flow and direction.  
• Resistance Swimming:  Hydrotherapy pools may come with a counter current unit to allow for resistance swimming - an endless swimming experience in one spot for recovery and rehabilitation. 
• Exercise: Underwater cycling and treadmills are becoming popular ways to gently rehabilitate 
• Seating: Hydrotherapy pools often have less seating and more room for standing, floating or supported movement.  
• Accessibility:  Hydrotherapy pools are designed with rehabilitation in mind and will usually have better accessibility options such as sunken stairs, hoists or ramps to help a user access the pool. 
• Location:  Hydrotherapy pools are commonly found at physiotherapy clinics, sports clubs, healthcare settings where the focus is recovery rather than relaxation. 

What are the key differences between a hot tub and a hydrotherapy pool?

Purpose

Hot tubs are designed primarily for relaxation, leisure, and general wellbeing, while hydrotherapy pools are usually intended for therapeutic use, supporting pain management, rehabilitation, and recovery.

Temperature

Hot tubs are typically maintained at slightly higher temperatures than hydrotherapy pools. A hydrotherapy pool, however, may offer variable temperature settings, enabling treatments such as contrast therapy.

Size and Depth

Hot tubs are generally smaller, with a focus on seated immersion. SpaFlo standard hot tub sizes are 2.0m and 2.4m, with a 1m height above ground.  Hydrotherapy pools, however, are often deeper and wider to accommodate exercise, stretching, and physiotherapy routines. 

Jets and Water Flow

Hot tub jets are primarily designed for comfort and relaxation. They create soothing streams of warm water that gently massage the body, providing a calming spa-like experience. Many hot tubs allow some level of adjustment, such as changing the pressure or redirecting the flow, but the main goal is always relaxation rather than rehabilitation.

Hydrotherapy pool jets, are engineered with therapy and exercise in mind. They can be positioned to target specific muscle groups or areas of the body, helping with pain relief and recovery. The flow and intensity are often highly adjustable, making them suitable for different therapeutic needs from gentle support for someone in rehabilitation, to more powerful resistance for athletic training. Some hydrotherapy pools also feature counter-current systems, enabling users to swim, walk, run and even cycle against a current for cardiovascular exercise or resistance-based physiotherapy.  

This makes hydrotherapy pool jets far more versatile than those in a hot tub: they’re not only about relaxation, but about healing, strengthening and active recovery.

Health Benefits

Hot tubs are primarily linked to lifestyle and wellness benefits. The warm water and gentle massage from the jets encourage relaxation, reduce stress, and help to ease general muscle tension after a long day. Many people also find that regular use improves sleep quality, as the drop in body temperature after leaving a hot tub helps trigger the body’s natural sleep response. In short, hot tubs contribute to a sense of wellbeing and can support everyday stress management.

Hydrotherapy pools have a more therapeutic and clinical application. They are widely used in hospitals, rehabilitation centres, sports clubs, and physiotherapy practices because the combination of warm water, buoyancy, and resistance creates an ideal environment for recovery. Exercising in water reduces the strain on joints, making it particularly effective for those with arthritis, mobility challenges, or recovering from surgery. 

Hydrotherapy pools also aid in pain relief, improved circulation, faster injury recovery, enhanced mobility, and athletic conditioning. For athletes, they are often part of structured rehabilitation and training programmes, helping to accelerate healing while maintaining fitness.

Cost and Investment

Hydrotherapy pools generally represent a larger investment than hot tubs, owing to their size and specialist design. However, the final cost depends on the level of customisation and features required.  Here at SpaFlo we design and build custom stainless steel hot tubs and hydrotherapy pools to our customers exact specification.  This could mean a custom shape or size, or it might mean lots of unique customisations such as targeted jets, lighting, steps, entertainment systems, retractable covers, glass fronts and more.  The customisation options are very broad for both hot tub spas and hydrotherapy pools, so speak to us about your requirements.  Our luxury bespoke stainless steel hot tubs start around £26.5k + VAT and hydrotherapy pools will have a slightly higher starting price, depending on size and features.

Hot tub or hydrotherapy Pool; which one is right for you?

Deciding whether a hot tub or a hydrotherapy pool is right for you really comes down to your intended usage.  If relaxation, stress relief and general leisure are your main purpose for investing in a spa then a hot tub might be perfect for you.  

If you have health, rehab or recovery as your longer-term goal then it might be better to opt for a hydrotherapy pool which can provide a wider range of health-based customisations.  

Whilst hydrotherapy pools are increasingly popular at home as a luxury leisure feature, we more commonly find hydrotherapy pools being sought after by commercial spas, healthcare clinics, physiotherapists, athletes and people with specific health conditions who would benefit from hydro therapy.  Learn more about hydrotherapy and how a hydrotherapy pool works in our blog.

SpaFlo Hot Tubs and Hydrotherapy Pools

SpaFlo design and manufacture bespoke stainless steel hot tubs and hydrotherapy pools for private and commercial clients all over the UK and beyond.  Whether it be a hot tub spa or a hydro pool, we can provide any level of customisation to make the pool truly fit for purpose.  

We often retro-fit counter current resistance swimming machines into existing pools and hot tubs - this is a possibility as long as the pool or spa has enough space for swimming on the spot.  We can also customise each pool with bespoke seating, jets, lighting, music systems, steps, entrance systems and more. 

If you would like to learn more, or are interested in a custom hot tub spa or hydrotherapy pool, get in touch with Richard and the team at SpaFlo.