Short answer: Choose multi-split when rooms are reasonably close together and there is one sensible outdoor position: it is tidier and often similar in price. Choose separate single systems when rooms are far apart, when you want each room fully independent, or when you might add rooms one at a time.
Advantages of multi-split
One outdoor unit instead of several, fewer wall penetrations outside, and often lower total cost for two or three nearby rooms.
Advantages of separate systems
Shorter pipe runs, full independence, and one fault never affects other rooms. Easier to add rooms later.
Mode limitation
All indoor units on one outdoor unit run in the same mode, all cooling or all heating. That rarely matters at home.
Related services
Multi-split air conditioningTwo to five rooms run from one outdoor unit, each with its own temperature setting.Learn moreWall-mounted air conditioningOne quiet indoor unit high on the wall, one outdoor unit outside. The most common way to cool, and heat, a single room.Learn moreDucted air conditioningHidden units in the loft or ceiling void, with only slim grilles on show.Learn more
More guides
- How much does air conditioning cost to install in the UK?
- How much does air conditioning cost to run?
- What size air conditioner do I need?
- Fixed split or portable air conditioning?
- Do you need planning permission for air conditioning?
- The £2,500 grant for air-to-air heat pumps explained
- F-gas rules: what homeowners need to know
- R32, R410A and R22: refrigerants explained
- Is air conditioning the same as a heat pump?
- What happens on air conditioning installation day
- Air conditioning noise and your neighbours
- Looking after your air conditioning: an owner's checklist
- Can you fit air conditioning in a listed building?
- Air conditioning in a flat: leases, freeholders and planning
- Keeping a home cool in a heatwave
Reviewed October 2026. Rules and prices change; check the date and ask us if anything is unclear.