What Is a Shortfall Case?
A shortfall case (Mangelfall) in German child support law occurs when the obligor's adjusted net income is insufficient to meet all support obligations while still retaining the legally mandated self-retention amount. In simple terms, there is not enough money to go around. The obligor cannot pay full support to all dependants without falling below the subsistence minimum themselves.
Shortfall cases are more common than many people assume. They affect not only low-income obligors but can also arise when a middle-income earner has three or more children, especially if a spousal support obligation exists simultaneously.
When Does a Shortfall Case Occur?
A shortfall case is triggered when the following calculation yields a negative result: adjusted net income minus self-retention minus total full support obligations. If the result is negative, the total obligations exceed what the obligor can afford.
For example, consider an employed obligor with an adjusted net income of 2,200 euros and two minor children aged 4 and 9. The self-retention is 1,450 euros. The full support for the 4-year-old is 355 euros (needs rate 480 euros minus 125 euros child benefit offset), and for the 9-year-old it is 426 euros (551 minus 125). Total support is 781 euros. Remaining income after support: 2,200 minus 781 equals 1,419 euros, which is below the self-retention of 1,450 euros. A shortfall case exists.
How Is Proportional Reduction Applied?
Once a shortfall case is identified, the available distributable amount must be calculated. This is the obligor's adjusted net income minus the self-retention amount: 2,200 minus 1,450 equals 750 euros.
This 750 euros is then distributed among the dependants in proportion to their full entitlements. Child A is entitled to 355 euros and Child B to 426 euros, for a total of 781 euros. Child A's share is 355 divided by 781, which is approximately 45.5 percent. Child B's share is approximately 54.5 percent.
Applied to the available 750 euros: Child A receives approximately 341 euros (instead of 355), and Child B receives approximately 409 euros (instead of 426). Both children receive less than their full entitlement, but the reduction is proportional and fair.
Priority Rules in Shortfall Cases
The proportional reduction applies only among dependants of the same priority rank. Under section 1609 of the Civil Code, minor children hold rank 1. If the shortfall affects only rank-1 dependants, the proportional reduction is applied among them.
If there are also rank-2 dependants (such as a divorced spouse), they receive nothing until all rank-1 dependants are fully satisfied. Only when the obligor's income exceeds the combined full entitlement of all rank-1 dependants plus the self-retention will any surplus flow to rank-2 claimants.
This strict priority system can have harsh consequences for divorced spouses. A spouse who was counting on spousal support may receive nothing if the obligor's child support obligations consume all available income above the self-retention threshold.
Practical Implications and Example
Consider a more complex scenario: an employed obligor earning 2,800 euros net, with three minor children (ages 3, 8, and 14) and a divorced spouse claiming spousal support. The self-retention toward minor children is 1,450 euros. The three children's full entitlements total approximately 1,206 euros (355 plus 426 plus 520 minus 125 per child in the relevant groups, adjusted for three dependants).
Available amount: 2,800 minus 1,450 equals 1,350 euros. Since 1,350 euros exceeds the total child support of 1,206 euros, all three children receive their full entitlement. The remaining 144 euros would theoretically be available for spousal support, but the spousal self-retention is 1,600 euros. Since the obligor's remaining income after child support (2,800 minus 1,206 equals 1,594) is below 1,600 euros, no spousal support is payable.
What Can the Obligor Do?
Obligors in a shortfall case should first ensure that their adjusted net income is correctly calculated. Over-generous deductions can sometimes be challenged, but conversely, legitimate deductions that were overlooked can reduce the calculated income and thus the obligation.
If the shortfall persists, the obligor should seek a formal modification (Abänderung) of any existing support order. Continuing to pay amounts that are unsustainable leads to debt accumulation and enforcement problems. A modification proceeding adjusts the support to the obligor's actual financial capacity and provides legal certainty for all parties.