About 803 €/month, every month, for eighteen years.
The shape of 18 years
A child is not one expense. It is a curve.
Monthly outflow per year of the child's age. Direct cash in cyan; childcare in violet, concentrated in the first years. The teen years rise quietly but never spike like the early ones.
Direct cashSource: Destatis - Konsumausgaben von Familien für Kinder, EVS 2018 (Tab. 2.1 + 3.1)
What it could have been
The same money, invested instead.
If you set aside 803 €/month in a globally diversified portfolio at a 6% real return, after 18 years you would hold roughly:
310.915 €
At 6% real return · 173.376 € contributed, 137.539 € from compounding
About 1.8× the direct cost.
This is the opportunity cost in plain numbers. It is not an argument against children. It is the size of the choice you are making, so you can plan around it: a savings goal, an 18-year compounding account in the child's name, or simply a clearer head.
For scale
What else costs about 173.376 €?
A down payment on a home · 80.000 €2.2×
A luxury car · 95.000 €1.8×
Seed capital for a small business · 200.000 €0.9×
Ten years of rent in a major city · 200.000 €0.9×
A full K-12 private school education · 250.000 €0.7×
Where the monthly cost goes
One child, one school month, eight buckets.
Monthly direct cash for one child, broken down by the cost table. Housing share and food dominate; phone and internet round to zero because they are typically already on the household plan.
Food122 €
Clothing60 €
Housing share179 €
Household & home37 €
Health (out-of-pocket)49 €
Transport59 €
Phone & internet27 €
Leisure & culture127 €
Education & childcare25 €
Restaurants & accommodation55 €
Other goods & services45 €
See all scenarios at once
1 child
174.096 €
174.096 €
2 children
291.168 €
291.168 €
3 children
403.920 €
403.920 €
Partner spotlight · True WealthPartner link
Open an account in the child's name.
Setting aside 10% of the child's costs is 80 €/month. Open an account in the child's name and turn the 18-year horizon into the longest compounding window you'll ever have. True Wealth invests it on autopilot: globally diversified ETFs, automatic rebalancing, no stock picks.