Living together and stopping alimony? 7 tips for successful proof
Month after month, you pay spousal support. But through friends, family, or social media, you receive signals that your ex-partner has long since started a new relationship — and perhaps is even living with someone. The sense of injustice gnaws at you. Yet you do nothing, because how do you prove something like that?
This article explains why hiring a private investigator is by far the most effective step in this situation, what an investigation costs, and how to take legal action afterward.
When does spousal maintenance stop upon cohabitation?
Not everyone knows this, but the law is clear here. Based on Article 1:160 of the Civil Code Spousal maintenance ends by operation of law the moment the maintenance recipient cohabits with a new partner as if they were married. This means: a lasting affective relationship and a shared household.
The problem? The burden of proof lies with you as the paying party. You must demonstrate that you are living together — and that is precisely where most people get stuck. Gathering evidence yourself is legally risky, emotionally draining, and often unusable in court.
7 reasons why a private investigator is the smartest choice
1. A private detective works completely anonymously
As soon as your ex-partner realizes that an investigation is being conducted into him or her, there is a high probability that behavior will be adjusted and evidence will disappear. A professional detective agency such as Strongwood operates under strict confidentiality and never stands out. Discretion is not an extra service — it is the foundation of every good investigation.
2. Access to research methods that you do not have
A certified private investigator has access to legal tools, OSINT methods, and professional databases that are inaccessible to private individuals. Think of combining public records, vehicle data, and social media analysis in a way that is legally sound. That is a completely different level than searching on Instagram yourself.
3. Specialization in alimony research makes the difference
Not all evidence counts for the judge. What the judge wants to see in proceedings under Article 1:160 of the Dutch Civil Code is very specific: proof of a lasting relationship, a shared household, and the so-called living percentage. A specialist in this field knows exactly which facts you need and how to record them. Read on the Strongwood alimony research page how they apply this methodology as founders.
4. Professional observation that stands up in court
Surveillance is a specialized field. A trained observer works exclusively in publicly accessible locations, meticulously records everything, and operates in accordance with the Private Security Organizations and Detective Agencies Act (Wpbr) and the GDPR. Following someone yourself yields unusable—and sometimes even criminal—evidence in most cases.
5. An official report that the judge accepts
The end product of a professional alimony investigation is an official report: structured chronologically, complete with photos, logbooks, and the agency's POB number. This is the type of evidence lawyers take to court. Strongwood has lawyer references who know exactly how this report works in the courtroom.
6. Digital and social media research as an additional weapon
People share more than they think. Shared check-ins, photos with new partners, merged social media profiles — a private investigator analyzes this in a structured, reproducible manner. That is quite different from saving screenshots yourself and hoping the judge finds that sufficient.
7. Less stress, faster clarity
Trying to prove on your own for months that your ex is cohabiting costs you energy, sleep, and peace of mind. A professional investigation provides clarity quickly — in most cases, after a targeted preliminary investigation. Since 1997, Strongwood has had a success rate of over 96.11% in these types of cases.
How much does a maintenance assessment cost?
The cost of an alimony investigation varies significantly by agency. Market rates range roughly between €3,500 and €89,500 — a huge range that stands or falls with the approach, experience, and transparency of the agency.
Strongwood works with a fixed price, linked to the amount of your spousal maintenance, so that you never pay more than you earn back. On partneralimentatie.com You will find a complete overview of the rates, including the preliminary research which is included as standard at no extra cost.
Good to know: in practice, the costs of the investigation can be recovered from the ex-partner through the court, or divided between both parties.
From report to termination: how does that work legally?
Has the investigation shown that your ex is cohabiting? Then there are two routes. Your lawyer first sends a letter to your ex-partner stating that spousal maintenance stops immediately — in many cases, this is sufficient. If the ex-partner is unwilling to cooperate, the lawyer submits the report to the court with a request for termination or a reduction to zero.
Strongwood has helped shape case law in this area in several cases — including regarding the recovery of already paid spousal maintenance and the acceptance of the housing percentage as a method of proof.
What should you look for when choosing a private investigation agency?
Not every desk is the same. Pay attention to the following points when making your choice:
Permit: The agency must possess a valid POB number issued by the Ministry of Justice and Security. Strongwood operates under license number POB809.
Experience in alimony cases specifically: Generic detective agencies lack the legal specialization required for proceedings under Article 1:160 of the Dutch Civil Code.
Fixed price or hourly rate: Always ask for a transparent quote in advance. A reliable agency prefers to work with fixed prices.
Demonstrable success rate: An agency that has been active in this field for decades can show you results.
Aftercare and network of lawyers: A good firm has contacts with specialized family law attorneys who are familiar with the report and can work with it.
Do you have questions, or do you want to know if an assessment has a chance of success in your situation? Contact Strongwood for a no-obligation consultation.
