Solo with a child: how one income carries a household over ten years

A Kindergeld calculator shows you one number. A Unterhaltsvorschuss calculator shows you another. Neither shows you what happens when your one income stays the household's only support for ten years. Two single parents, two very different starting points.

As a single parent, one income carries what two people would carry in other households. There's no second paycheck to catch a gap when daycare fees rise, rent goes up, or child support doesn't arrive. That's exactly why no single calculator is enough here: the question is never just how much Kindergeld (child benefit) there is or which tax class applies, but how all of it plays out together over the years, when there's only one income source to catch everything.

The figures below are model calculations based on plausible example assumptions. Income, place of residence, and family situation interact differently for every household. Miravel works with your own numbers.

Why a single calculator isn't enough for single parents

A Kindergeld calculator answers one question: how much child benefit do I get per child? A Unterhaltsvorschuss (advance maintenance payment) calculator answers another: how much does the state pay when the other parent doesn't pay, or doesn't pay regularly? A gross-to-net calculator answers a third: how much of my salary is left in tax class two? None of these calculators connects the answers. In a single-parent household, that connection is precisely the real question, because there's no second income to make up for it when one of the answers turns out worse than expected.

Then there's the timeline. Kindergeld runs until adulthood or longer, Unterhaltsvorschuss is tiered by age and time-limited, a child eventually outgrows daycare and then, before long, afternoon care at school, which changes childcare costs. A household with one income feels every one of these shifts more directly than a household with two.

Two single parents, same income, different maintenance situation

Jana and Sema both work full time, both earn around €2,900 gross a month, and each have one child of primary-school age (6 to 11 years old). The decisive difference isn't their own income, it's whether the other parent pays.

Same income, different second source

Jana: when the other parent pays reliably

What the Miravel model works out for Jana's household on tax class and Kindergeld: on a gross income of €2,900 in tax class two, which factors in the Entlastungsbetrag für Alleinerziehende (the tax relief for single parents), around €2,100 net a month is left. Add €259 in Kindergeld for one child. Together with a privately agreed maintenance payment of an assumed €480, the available household income comes to around €2,843 a month.

This calculation looks comfortably stable, as long as one condition holds: the other parent keeps paying. That's exactly the point a Kindergeld calculator doesn't show, because it doesn't know about maintenance at all, and a maintenance calculator doesn't show, because it doesn't factor in the tax class or the Kindergeld. If the maintenance payments stop, Jana's household shifts toward Sema's situation, often from one month to the next, with no warning.

Sema: when Unterhaltsvorschuss is the second pillar

Sema has the same gross income and the same tax class as Jana, plus the same Kindergeld. The difference: instead of private maintenance, she receives Unterhaltsvorschuss, a state benefit for single parents whose child gets no maintenance, or no regular maintenance, from the other parent.

• Own net income: around €2,100 a month, same as Jana
• Kindergeld: €259 for one child
• Unterhaltsvorschuss: tiered by the child's age, €227 a month (ages 0 to 5), €299 (ages 6 to 11), or €394 (ages 12 to 17); the full Kindergeld is already deducted from these amounts
• Available household income for a child aged 6 to 11: around €2,662 a month

Unterhaltsvorschuss is legally tiered by age and generally available until the child's eighteenth birthday. That means: Sema's second income pillar is more predictable than maintenance, which can stop coming, but its amount changes as the child gets older, it isn't a payment that stays the same size forever. Anyone who doesn't plan for that shift over the years gets surprised by it, not because the benefit disappears, but because it changes.

What this calculation really shows

approx. €180 — Modeled difference in available household income between Jana (with regular maintenance) and Sema (with Unterhaltsvorschuss for a child aged 6 to 11), with otherwise identical income and tax class. The difference isn't in their own earnings, it's in the second income source, and it shifts with the child's age between roughly €85 and €250.

Both households have the same own income, the same tax class, the same Kindergeld entitlement. The entire difference comes down to a single variable: whether the other parent pays or not. That's exactly where isolated calculators fail, because each of them only shows one slice. A household with one income has no buffer that makes this difference invisible.

Over ten years, another shift comes into play that individual calculators also miss: Kindergeld and Unterhaltsvorschuss change with the child's age, childcare costs drop with the move to school, but afternoon care or hobbies can bring new costs. And across the working years, only one income accumulates pension points, not two. Anyone who doesn't see these shifts together, but looks them up one after another in different calculators, loses exactly the perspective that matters most for a one-income household: how the whole picture holds up over the years, not just a single month.

What can actually be changed about this calculation

A household with one income has fewer levers than a two-earner household, but it has some, and they're only visible once you know the whole picture, not just one slice:

• Enter the tax class and the Entlastungsbetrag für Alleinerziehende correctly, so your own net income isn't unnecessarily low
• Check early whether Unterhaltsvorschuss can be applied for, instead of waiting on irregular private maintenance
• Keep an eye on your own pension trajectory over the working years, since only one income is accumulating pension points
• Plan childcare costs across the child's years, not just for the current year
• Build a buffer for the case that private maintenance stops or comes irregularly

Which of these levers actually helps depends on your own income, the child's age, and how reliable the maintenance payments are. That's not something you can look up in three separate calculators, it needs a calculation that models income, Kindergeld, maintenance or Unterhaltsvorschuss, and household buffer together over the years.

Why the whole picture makes the difference here

Miravel doesn't treat Kindergeld, maintenance, and tax class as separate questions. It simulates your entire household over the years: income, tax burden, Kindergeld, pension points, household buffer, all together, at every point on the timeline. For a household with one income, that isn't a nice-to-have, it's the only way to see a gap before it becomes a problem.

Your data stays in your browser throughout. Miravel doesn't tell you how to organize your household. It shows you what happens with your own numbers over the coming years.

Frequently asked questions

How much is the Entlastungsbetrag für Alleinerziehende, and does it apply automatically?

The Entlastungsbetrag für Alleinerziehende is a tax allowance that lowers taxable income and so raises net income. It doesn't apply automatically, it has to be claimed through tax class two or on your tax return. Anyone who doesn't enter it pays unnecessarily more tax, and that doesn't correct itself.

What happens if maintenance payments suddenly stop?

If the other parent stops paying, or pays irregularly, Unterhaltsvorschuss can generally be applied for at the responsible Jugendamt (youth welfare office), a state replacement benefit tiered by the child's age: €227 a month for ages 0 to 5, €299 for ages 6 to 11, €394 for ages 12 to 17, each after deducting the full Kindergeld. A household that hasn't run the numbers on this transition ahead of time often experiences it as an abrupt income drop, even though a replacement benefit exists.

Up to what age of the child is Unterhaltsvorschuss available?

Unterhaltsvorschuss is generally available until the child's eighteenth birthday. The amount rises with the child's age in three tiers (0 to 5, 6 to 11, 12 to 17 years), with the full Kindergeld deducted from the underlying minimum maintenance amount each time. For children aged 12 and up, additional conditions apply, for example around the income of the parent providing care.

Does a single-parent household accumulate fewer pension points than a two-earner household?

Yes, structurally, because in a one-income household only one person works subject to social security contributions and accumulates pension points, while in a two-earner household potentially two people do. Child-raising credit periods make up for some of that, but they don't replace an ongoing second income. Anyone who sees this gap over the decades, rather than noticing it only shortly before retirement, has more time to close it.

Why isn't a single Kindergeld or maintenance calculator enough?

A Kindergeld calculator only knows the child-benefit entitlement, a maintenance calculator only the maintenance situation, a gross-to-net calculator only the tax class. None of them shows how these three factors develop together over the years, as the child's age, childcare costs, and your own employment situation change. For a household with one income, that combined development is exactly the question that matters.

Miravel simulates your whole household picture, across years and across several income sources at once: salary, Kindergeld, maintenance, pension points. Not just one number in isolation. Start now for free.