What Is Adverse Possession? Know Before You Lose Your Land!

Adverse possession refers to the act of occupying someone else’s property—whether real estate or movable assets. According to Section 1382 of the Thai Civil and Commercial Code, "A person who possesses another's property peacefully and openly, with the intent to own it, shall gain ownership if it is real estate and has been possessed continuously for ten years, or if it is movable property and has been possessed for five years."  This means that if someone takes possession of your land under these conditions, they may legally acquire ownership.

According to the law, a person must meet all three criteria to successfully claim adverse possession of a property:

1. Peaceful and Open Possession

The occupation of the land must be peaceful and visible to the public. For example, the person must have built a permanent house or structure, lived there openly, and used the land as their own—not in a secretive or hidden manner.
If the legal owner never attempts to evict the occupant, the claim may be valid. However, if the owner demands the person to leave, files a police report, or takes legal action, then the possession is no longer considered "peaceful." In such cases, the occupant may be charged with trespassing, which carries a penalty of up to one year in prison, a fine of up to 20,000 baht, or both.

2. Intent to Own the Property

A person claiming adverse possession must clearly demonstrate their intention to own the land. This means they must use the property as if it belongs to them, exercising full control over it and preventing others from using it. Simply occupying the land is not enough; the occupant must act as the rightful owner.
However, adverse possession cannot be claimed if the legal owner has given permission to use the land, such as through a rental agreement, a caretaker arrangement, or shared ownership. Similarly, if someone is managing the land on behalf of an heir or another rightful owner, their possession does not count, regardless of how long they have occupied the property.

To establish adverse possession, the occupant must formally declare their intent to take ownership. This can be done through verbal notification or, preferably, in writing to the legal owner. Without this declaration, the law still considers them to be using the property on behalf of the owner rather than as an independent possessor.

According to Section 1381 of the Thai Civil and Commercial Code, if someone holds property as a representative of the rightful owner, they can only change their status by informing the owner that they no longer intend to hold it on their behalf or by obtaining new ownership rights through a separate legal agreement.

3. Continuous Possession for More Than 10 Years

To claim adverse possession, the occupant must have continuously possessed the land for at least 10 years in the case of real estate and 5 years for movable property. This means the possession must be uninterrupted and consistent throughout the required period.

Merely using the land for a short time does not qualify. For example, if someone plants trees on the land but never returns to maintain or use it, this does not establish continuous possession. Furthermore, if the occupant stops using the land for a certain period, the time count resets, and they must start the 10-year or 5-year period again once they resume possession.

Even if someone meets all the legal criteria—peaceful and open possession, intent to own, and continuous use for 10 years—it does not necessarily mean they can successfully claim ownership. The ability to acquire land through adverse possession also depends on the type of land title or ownership document.

Only land with a full ownership title deed (such as Nor Sor 4 or land under a pre-emptive certificate) can be subject to adverse possession. In contrast, land without a title deed or land classified under Nor Sor 3, Nor Sor 3 Gor, or Sor Por Kor 4-01 cannot be claimed through adverse possession. These types of land grant only possessory rights, meaning the holder does not legally own the land and therefore cannot lose it through adverse possession.

However, landholders must still be cautious. If someone takes possession in a peaceful and open manner, with the intent to claim ownership for at least one year, they may attempt to assert possessory rights. In such cases, the original possessor has one year from the date of dispossession to file a legal claim to reclaim their rights.

Additionally, certain types of land can never be acquired through adverse possession, regardless of how long they have been occupied. These include public land, state property, monastic land, and land owned by the Crown Property Bureau. Even after more than ten years of occupation, adverse possession laws do not apply to these properties.

Protecting your land from adverse possession requires regular monitoring and proactive measures. Here are key steps to ensure your property remains secure:

1. Regularly Inspect Your Land

One of the easiest ways to prevent adverse possession is by routinely checking on your property. If you own unused land, especially if it is undeveloped or in a remote area, it is at higher risk of being encroached upon. Visit the property at least once a year to look for signs of unauthorized use, such as newly built structures or evidence of habitation.

2. Communicate with Neighbors

Your neighbors can be a valuable source of information about any unusual activity on your land. Ask them if they have seen anyone using your property in your absence and provide them with your contact details. This way, they can notify you immediately if they notice unauthorized use.

3. Install Fencing and Warning Signs

Clearly marking your land boundaries is crucial, especially if your property is adjacent to others. A fence helps prevent unintentional encroachment, such as neighbors mistakenly assuming part of your land is theirs. Additionally, posting visible warning signs like “No Trespassing” or “Private Property” reinforces your ownership and deters unauthorized use. Regularly check that fences and signs remain intact and have not been removed or damaged.

4. Take Action Against Trespassers Immediately

If you discover someone using your land without permission, address the issue right away. Do not wait until their possession reaches 10 years. Start by speaking with them to resolve the situation. If they refuse to leave, file a police report for trespassing. Law enforcement can intervene, and if the issue persists, gather evidence and proceed with legal action through the courts.

5. Use Written Agreements for Authorized Use

If you allow someone to use your land—whether for temporary residence, as a pathway, or for other purposes—always have a written agreement. Documents such as lease agreements, rental receipts, mortgage contracts, or land-use permits clearly establish that their presence is with your consent. These records can prevent future disputes over ownership claims.

6. Survey the Land Every Five Years

Even if your land is fenced, boundary disputes can still arise. For example, a neighbor might move a fence post slightly over time, reducing the size of your property. If you rarely visit the land, you might not notice until it’s too late. To avoid this, conduct a professional land survey at least every five years to confirm that your property’s boundaries remain unchanged and that all boundary markers are intact and correctly positioned.

By taking these precautions, you can significantly reduce the risk of losing your land to adverse possession and protect your ownership rights.

Adverse possession does not become legally valid until a court issues a ruling granting ownership right. Only after this ruling can the adverse possessor request a name change on the title deed at the Land Department. To claim ownership, the person in possession of your land must file a petition with the court, providing evidence to support their claim. However, before the court makes a decision, you, as the legal owner, will receive a court notice.

At this stage, you have the right to object to the claim. If you fail to contest it, the court may rule in favor of the possessor, granting them legal ownership through adverse possession. While it is still possible to file a lawsuit afterward to reclaim the land, the chances of success are low. You would need to prove that the possession was unlawful, which can be difficult.

Adverse possession is a common issue, often affecting people who are unaware that their parents once bought land or who forget about their own land purchases. By the time they realize it, they may have already lost their property. To avoid this risk, it is essential to regularly check on your land, visit it at least once a year, and take necessary precautions. Don’t neglect your property—otherwise, someone else might claim it before you even realize it!