Geothermal heating in Finland
A ground-source heat pump takes heat from a borehole or a ground loop into a water-based heating system. Drilling the borehole needs a municipal permit before any work starts.
Lämpöopas lists 70 companies across 19 cities, and 29 of them carry a Tukes register entry.
Company and city counts come from the Lämpöopas directory itself, checked 3 September 2026.
Who may install it
Only a refrigeration business entered in the Tukes register, with certified fitters, may install or service the refrigerant circuit. The electrical connection may only be made by an electrical contractor entered in the Tukes contractor register with a named person in charge of electrical work.
Statute: EU 517/2014; ympäristönsuojelulaki 527/2014; sähköturvallisuuslaki 1135/2016Tukes registers
The household tax credit is available only if the company that did the work was in the prepayment register at the moment the invoice was paid. If it was not, no credit is given at all — not even when the work was subcontracted to a registered company. Checking is the payer’s duty, and the register entry is public in YTJ.
TVL 127 b §Verohallinto, 10 February 2026
Geothermal heating, 19 cities
Cities with at least three installers listed. The number is real, not an estimate.
- Helsinki18installers
- Vantaa18installers
- Espoo14installers
- Tampere13installers
- Järvenpää9installers
- Hyvinkää6installers
- Kerava6installers
- Oulu6installers
- Tuusula6installers
- Kirkkonummi5installers
- Lohja5installers
- Porvoo5installers
- Jyväskylä4installers
- Kangasala4installers
- Lahti3installers
- Lappeenranta3installers
- Pirkkala3installers
- Sipoo3installers
- Turku3installers
A further 1–2 installers are listed in these cities: Heinola, Hollola, Imatra, Joensuu, Kauniainen, Kempele, Kouvola, Kuopio, Kuusamo, Lempäälä, Loviisa, Nokia, Nurmijärvi, Pornainen, Raisio, Rovaniemi, Varkaus, Vihti, Ylöjärvi.
What the numbers say
In 2025 about 112,000 heat pumps were delivered to the Finnish trade, about 7,000 of them in this equipment group.
Deliveries then grew 63% year on year in the first half of 2026; SULPU names a cold winter and the start of the air-to-air replacement market as the drivers.
Demand peaks: April, May and June. The timing is what installers say, not a recorded statistic.
What installers say
Frequently asked questions
Can I claim the household tax credit on the installation?
Household tax credit: 35% of the labour share of a company invoice, up to €1,600 per person per year, with a €150 own share (Verohallinto, 10 February 2026). The government has proposed raising this to 40% and €2,100 for 2026–2027, retroactively from 1 January 2026 (HE 113/2026 vp, Eduskunta, 11 June 2026). Parliament has not passed the bill, and the tax administration still writes about it in the conditional (Verohallinto, 16 June 2026).
Sources:Verohallinto, 10 February 2026; Eduskunta, 11 June 2026; Verohallinto, 16 June 2026
Is there still a grant for giving up oil heating?
The grant is closed. Applications ended on 25 May 2026 at 16.15, the appropriation was spent in full and over 300 applicants received nothing. It used to pay €4,000 / €2,500 depending on the replacement system (Elinvoimakeskus, 1 September 2026). Giving up oil heating altogether carries an elevated credit of 60% of the labour share, up to €3,500 per person, in force until 31 December 2027 (Verohallinto, 10 February 2026).
Sources:Elinvoimakeskus, 1 September 2026; Verohallinto, 10 February 2026
What seasonal efficiency should I expect?
It is set by the distribution temperature, not by the brand: 3.4 on 30 °C underfloor heating, 2.5 on a 60 °C radiator circuit, and 2.3 for domestic hot water (Ympäristöministeriö, 20 December 2017). That is the running cost difference the emitters make before any brand comparison. The pump is sized to part of the peak load, so 1–5% of the annual energy still comes from a back-up resistor at a coefficient of one (Motiva, 16 February 2026).
Sources:Ympäristöministeriö, 20 December 2017; Motiva, 16 February 2026