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NorwayPublic sector2020 – ongoing

Norwegian Tax Administration

Machine learning for undeclared rental-income checks and guidance

Norway's tax administration attributed over NOK 110 million in additional declared income to a rental model and follow-up measures

WorkingCompany's own claim

Problem

Some owners of secondary homes did not report taxable rental income. The administration needed to direct checks and guidance toward likely omissions.

Approach

The administration developed an XGBoost model for tax year 2020 using information about owners and properties. It ranked owners by rental probability to support audit selection. The model also helped select recipients of information letters.

Results

over NOK 110 millionincrease in declared ordinary income attributed to the model and associated measures since deploymentCompany's own claim[1]

Takeaway

The reported income increase combined model-assisted selection with follow-up measures. It represented additional declared income rather than tax collected.

Categories

Business function
Finance, risk and legal
Innovation type
Process innovation
Evidence
Company's own claim

Sources

  1. Maskinlæringsmodell bidrar til å finne dem som ikke rapporterer utleie
    Norwegian Tax Administration1 Aug 2023Government publication

Source summaries

[1]Norwegian Tax Administration1 Aug 2023

The administration described its rental-probability model and its use in checks and guidance. It attributed over NOK 110 million in additional declared ordinary income to the model and related measures.

Full details are in the original sources.

Added 1 Nov 2026 · Updated 1 Nov 2026
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