Prime d'activité Simulator: French In-Work Benefit (CAF)

How the French prime d'activité is calculated: formula and example

The French prime d'activité (in-work benefit paid by the CAF or MSA) equals the household flat amount (€638.28 for a single person since 1 April 2026) plus 59.85% of earned income plus individual bonuses, minus household resources. Nothing is paid below €15 a month. For a single person earning €1,450 net who receives housing benefit, the tool estimates about €161 a month.

The formula used by the tool

Benefit = household flat amount + 59.85% of earned income + bonuses − household resources (earned income + other resources + housing deduction, deemed to be at least the flat amount)

• Flat amount: €638.28 for one person, increased by 50% for the second household member, 30% for the third and fourth, and 40% for each child beyond the second (a couple with one child gets 1.8 times the base).
• Individual bonus: zero below €687.35 net, rising to €181.19 from €1,426 net, computed for you and for your partner.
• Housing deduction (forfait logement): €76.59 (1 person), €153.19 (2) or €189.57 (3 or more), applied if you receive housing benefit, own your home or are housed free of charge.

Example

Single person, no children, tenant receiving APL, €1,450 net a month: 638.28 + 867.83 (59.85% of 1,450) + 181.19 − (1,450 + 76.59) = €160.71. The tool shows €161 a month, about €482 a quarter. Without housing benefit the deduction is dropped and the estimate rises to €237.

Limits

• The bonus follows the old scale. Since 1 April 2026 it can reach €240.63 and keeps rising between 1 and 1.15 times the minimum wage, so the tool underestimates around the SMIC.
• The single-parent increase is not modelled.
• This is a French benefit: only the CAF or MSA sets the amount actually paid, based on the average of three declared months.

Sources and dates: formula of article L842-3 of the French Social Security Code; €638.28 flat amount set by decree no. 2026-222 of 30 March 2026, in force from 1 April 2026; 59.85% rate from decree no. 2025-292 of 29 March 2025, applied since 1 April 2025; housing deduction from the CAF scale of 1 April 2026; the tool's bonus uses the April 2024 scale, official cap €240.63 since 1 April 2026 (service-public.gouv.fr guide, checked on 14/10/2026).

Frequently Asked Questions

How does the CAF calculate the prime d'activité?

It adds the household flat amount (€638.28 for a single person since 1 April 2026), 59.85% of earned income and the individual bonuses, then subtracts household resources, which are treated as at least equal to the flat amount. The calculation uses the average of the three months on the quarterly declaration, and nothing is paid below €15 a month.

Up to what salary can a single person get the prime d'activité?

With the tool's parameters, a single person without children who receives housing benefit stops qualifying at about €1,813 net a month, or about €2,004 without housing benefit. Since 1 April 2026 the bonus can reach €240.63, which pushes this threshold slightly higher, so check with the official CAF simulator.

What is the housing deduction (forfait logement)?

It is a fixed amount added to your resources if you receive housing benefit, own your home or live rent-free. From 1 April 2026 it is €76.59 for one person, €153.19 for two and €189.57 for three or more, and it lowers the benefit by the same amount.

What changed for the prime d'activité in April 2026?

The flat amount was raised by 0.8% to €638.28 by the decree of 30 March 2026, and the individual bonus can now reach €240.63, with a targeted increase between 1 and 1.15 times the minimum wage. The first effects show up in payments from summer 2026, depending on the declared quarter.

Is this tool really free?

Yes, all tools on Kristools are 100% free and accessible without registration.

Is my data protected?

Yes. All processing is performed directly and securely inside your browser. No personal data is sent to our servers.