Underpayment(redirected from underpay)
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The act of paying an amount under the full amount. For example, if one's mortgage payment is $600 per month but one only pays $400 for July, one has underpaid the mortgage. Underpayment is not sustainable and may lead to serious financial difficulties. However, paying what one can afford when one cannot pay the full amount may be easier for both the obligor and the obligee.