Non-EU/EEA foreign individuals and entities need a permission issued by the Ministry of Defence to buy real estate (land). Permission is also required of entities domiciled in the EU/EEA, but in which a non-EU/EEA individual or entity has ownership of at least 10% or equivalent effective influence in the entity buying the real estate. Permission may be granted if the transfer of real estate is not deemed to complicate the organisation of defence, the surveillance and safeguarding of territorial integrity or the assurance of border control, border security or the maintenance of emergency stocks of critical supplies. Furthermore, pursuant to the Act on Land Acquisition in Åland, legal or natural persons who do not enjoy regional citizenship in Åland may not acquire property on the Åland Islands without permission by the competent authorities of the Åland Islands.
On 1 January 2023, the Law 109/2022 amending the Act on transfers of real estate property requiring permission (470/2019) entered into force. The Law 109/2022 further specifies the personal scope of application (including exceptions to the permission requirement), attributes the Ministry of Defence additional powers to require information and modifies the conditions for the grant of the permission and reduces the time within which, following a refusal, the transfer of the property needs to take place.

"§ 1  Scope of the law and relationship to other legislation
This law applies to the acquisition of real estate in the territory of the Finnish state, if the transferee is:
1) an entity domiciled elsewhere than in the territory of a member state of the European Union or a state belonging to the European Economic Area, or a citizen of a state other than a member state of the European Union or a state belonging to the European Economic Area, or a person who does not have citizenship, whose citizenship is unknown or whose citizenship has not been reliably verified;
2) an entity with its registered office in the territory of a member state of the European Union or a state belonging to the European Economic Area, but where the natural person or entity referred to in paragraph 1 has at least one-tenth of the total number of votes of all the shares of the limited company or equivalent actual influence or equivalent influence in another entity or movement. [...]
§ 2 Licensed real estate acquisition
No permit is required if:
1) the transferor of the real estate is the recipient's married or common-law partner or a party to a registered partnership;
2) the transferor of the property is a person whose recipient could inherit according to the provisions of Chapter 2 of the Inheritance Act (40/1965); or
3) spouses, common-law partners or parties to a registered partnership acquire real estate together and one of them does not need a permit according to this law and his share of the real estate to be acquired is at least one tenth.
Permission is also not required if the transferor is the recipient's former married or common-law partner or a party to a registered partnership, the recipient already owns a share of the real estate subject to the transfer, and the transfer takes place no later than two months after the dissolution of the marriage or cohabitation or registered partnership.
In this law, common-law partners  mean persons who are not married to each other, but who live continuously in a joint household under conjugal conditions. [...]
§ 5 Conditions for issuing a permit
A permit for the acquisition of real estate is not granted if the acquisition can be assessed as threatening national security or complicating the organization of national defense, monitoring and safeguarding territorial integrity, or ensuring border control, border security or security of supply.
The application can also be rejected if the acquisition of real estate may jeopardize the benefits referred to in subsection 1 and:
1) it is obvious that the property to be acquired is not suitable for the purpose of use stated in the application; or
2) the transferee is a person who has received a legally binding deportation decision pursuant to Section 149 of the Aliens Act (301/2004) and who is staying in the country illegally. [...]" (Act on Transfers of Real Estate Requiring Special Permission (470/2019), last amended 20 December 2022, Sections 1, 2 and 5, as amended [unofficial translation and google translation])
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"Section 1 - Scope of application and relationship with other legislation:
This Act applies to transfers of real estate in the territory of Finland if the transferee is:
1) an entity with a seat in a state other than a Member State of the European Union or a member country of the European Economic Area or a citizen of a state other than a Member State of the European Union or a member country of the European Economic Area;
2) an entity with a seat in a Member State of the European Union or a member country of the European Economic Area when a natural person or entity within the meaning of the foregoing subsection 1 holds a minimum of one tenth of the aggregate number of votes carried by the shares of a limited liability company or exercises equivalent actual control in the company.
When the percentage of votes carried by the aggregate number of shares in a limited liability company referred to in subsection 1(2) above is determined, such a determination shall also include shares:
1) held by a company forming part of the same group of companies to which the transferee belongs;
2) held by a family member of the transferee or an entity or foundation in which such a family member exercises control; or
3) by virtue of which the transferee is entitled to exercise voting rights under a contract or other arrangement.
The provisions of the foregoing subsection 2 shall also apply, mutatis mutandis, to the determination of the transferee's percentage of votes in entities other than limited liability companies.
For the purposes of this Act, transfer of real estate means a legal act by which title to a piece of real estate or to a share of real estate or to a parcel of real estate is transferred to a new owner.
This Act shall not apply in the territory of the Province of Åland.
Section 2 - Transfers of real estate requiring special permission:
The natural person or entity within the meaning of the foregoing section 1(1) may only acquire a piece of real estate in the territory of Finland subject to special permission issued by the Ministry of Defence.
No such permission is required if:
1) the transferor of the piece of real estate is the married or unmarried spouse or registered partner of the transferee;
2) the transferor is a person that the transferee could inherit under chapter 2 of the Code of Inheritance; or
3) the piece of real estate is to be acquired by the transferor together with his or her married or unmarried spouse or registered partner and one of them is not required to have the permission referred to this Act.
[...]
Section 5 - Prerequisites for granting permission:
Permission for the transfer of a piece of real estate may be granted if the transfer is not deemed to complicate the organisation of defence, the surveillance and safeguarding of territorial integrity or the assurance of border control, border security or the maintenance of emergency stocks of critical supplies.[...]" (Act on Transfers of Real Estate Requiring Special Permission (470/2019), Sections 1, 2, 5 [unofficial translation])
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"Section 1:
In order to exercise the right of the people of Åland to own land in Åland, the restrictions provided for in this Act apply to the acquisition and management of immovable property in the province.
Section 2:
Those who do not have Åland's right of domicile, as well as companies, cooperatives, associations, other entities, institutions, foundations or associations, may not acquire or manage immovable property in the province without the permission of the provincial government. Exceptions to this may be provided by provincial law.
What is provided in this Act for the acquisition of immovable property also applies to the scope of the immovable property as well as the part of the estate acquired or controlled by the transfer which owns or controls the immovable property.[...]" (Act on Land Acquisition in Åland (3/1975), Sections 1 and 2 [google translation])
Act on Transfers of Real Estate Requiring Special Permission (470/2019), last amended 20 December 2022
Act on Transfers of Real Estate Requiring Special Permission (470/2019)
Act on Land Acquisition in Åland (3/1975)
[<a href="https://www.finlex.fi/en/laki/kaannokset/2019/en20190470.pdf">Act</a>],[<a href="https://www.finlex.fi/fi/laki/ajantasa/1975/19750003">Act</a>]