The short answer: choose a single-split when you mainly need to cool and heat one room, and a multi-split once you want three or more rooms comfortable from a single outdoor unit. Below we break down the cost, the trade-offs and the right pick for a T1, T2 or T3 in Greater Lisbon — then install it for you, F-gas certified and fully guaranteed.
Brought to you by the local team behind AC Rental Lisbon — years of keeping Lisbon homes and apartments comfortable.
Most people arrive thinking "multi-split must be the better one." It isn't better or worse — it's a different shape. A single-split is one room, one machine outside. A multi-split shares one outdoor unit across several rooms. Pick wrong and you either overspend on capacity you never use, or you clutter your façade with condensers you didn't need. The right call comes down to how many rooms you want comfortable and how much outdoor space you have — not the label.
Both are wall-mounted heat pumps that cool in summer and heat in winter. The difference is entirely in how many indoor units share the outdoor one.
Portuguese flats are sized by bedrooms (T1 = one bedroom, T2 = two, and so on). Here's how we'd usually advise — your building may nudge it either way, which is what the quote checks.
Go single-split. One well-sized unit (often 9,000–12,000 BTU) in the main room does the job, cheaply and simply. Open-plan studios only ever need one machine — from about €550 installed.
It's a toss-up. Cooling just the living room and one bedroom? Two single-splits are flexible. Want the whole flat comfortable with one machine outside? A two-unit multi-split is tidier. We price both.
Lean multi-split. Three or more rooms usually make one 3–4 unit outdoor condenser the better value and the tidier look — especially where façade space or condomínio rules limit how many units you can hang.
Rule of thumb: 1–2 rooms lean single-split, 3+ rooms lean multi-split. Outdoor space and historic-centre rules can override it — we check both before we quote.
You don't have to make the call alone. We size both routes, tell you honestly which fits, and handle the certified install end to end.
Area, number of rooms and your building type — about a minute in the form. That's all we need to start.
We work out single-split and multi-split for your place and send both, itemised, within one working day.
A vetted F-gas certified installer fits your pick cleanly — a single-split in a few hours, a multi-split over one to two days.
You're fully covered, warranty in writing. Need a service or another room later? We're a message away.
Indicative installed prices (unit + fitting) for Greater Lisbon in 2026. Lisbon and Cascais sit at the higher end. Your exact number comes from the free quote.
Annual maintenance (clean + gas check): ~€60–180 per unit. Prices are indicative guide ranges, not a quote. For the full breakdown see our AC installation price guide.
The single biggest driver. Two rooms often price similarly either way; from three, multi-split usually pulls ahead.
One condenser (multi) versus several (single) changes the fitting work — a tight façade favours multi-split.
Multi-splits run more copper from the shared unit; beyond the standard ~3 m it's charged per metre.
Daikin/Mitsubishi sit at the top; Gree/Haier are more affordable for the same rooms, single or multi.
If piping and holes already exist, either install can be 30–50% cheaper.
In Alfama, Baixa & Chiado, cutting to one outdoor unit (multi-split) can be what makes an install allowable.
From the historic centre to the coast and across the river — we fit both system types wherever quality installation matters.
Ready to move? Explore our multi-split installation service, our full AC installation options, or head back to the homepage to get a quote.
A single-split is one indoor unit connected to one outdoor unit — it cools and heats a single room. A multi-split connects two to four indoor units to just one outdoor unit, so you can climate several rooms while keeping only one machine on the façade or balcony. Single-split is simplest and best value per room; multi-split is tidier and often better value once you reach three rooms or more.
Not always. For two rooms, two single-splits often work out similar in price, and each can be replaced independently. From three rooms upward the multi-split usually wins: you pay for one larger outdoor unit instead of three, save space on the façade, and the run stays neater. In Lisbon, where balcony and façade space is scarce, that single outdoor unit is often the deciding factor.
For a T2 it is genuinely a toss-up. If you only really need the living room and one bedroom cool, two single-splits are simple and flexible. If you want the whole flat comfortable and have limited outdoor space, a two-unit multi-split keeps a single machine outside and looks tidier. We size both options in your free quote so you can compare the numbers.
Yes — that is its main advantage. A multi-split runs two to four indoor units from one outdoor unit, so there is a single condenser outside instead of one per room. In historic centres such as Alfama, Baixa and Chiado — where façade units are restricted — cutting to one outdoor unit can be the difference between an approvable install and none at all.
Only up to the outdoor unit's capacity. A multi-split is sized for a fixed number of indoor units, so if you might expand later it is worth sizing the outdoor unit with headroom from the start. If your plans are uncertain, single-splits added one at a time can be the more flexible route. We plan for this when we quote.
Both are heat pumps: they cool in summer and heat in winter with about three times less electricity than an electric heater. Efficiency per room is broadly similar; the choice is about layout and outdoor space, not warmth. A modern A++ system of either type keeps a Lisbon home comfortable all year on low running costs.
Tell us your flat — a T1, a T2, a top-floor with an awkward façade — and we'll tell you straight which system fits and roughly what it costs. No pressure, no jargon. We usually reply within minutes on WhatsApp.
Tell us your rooms and we'll size single-split and multi-split for your place, and send an honest quote within one working day. No obligation.