diff --git a/bill/payment.go b/bill/payment.go
index dec3d473..e643b91d 100644
--- a/bill/payment.go
+++ b/bill/payment.go
@@ -55,6 +55,7 @@ func (p *Payment) totalAdvance(zero num.Amount) *num.Amount {
 	for _, a := range p.Advances {
 		sum = sum.MatchPrecision(a.Amount)
 		sum = sum.Add(a.Amount)
+		a.Amount = a.Amount.Rescale(zero.Exp())
 	}
 	return &sum
 }
diff --git a/bill/payment_test.go b/bill/payment_test.go
index a9b27543..7e170e93 100644
--- a/bill/payment_test.go
+++ b/bill/payment_test.go
@@ -66,7 +66,7 @@ func TestPaymentCalculations(t *testing.T) {
 		p.calculateAdvances(zero, total)
 		a := p.totalAdvance(zero)
 
+		assert.Equal(t, "20.85", p.Advances[0].Amount.String())
 		assert.Equal(t, "20.845", a.String())
-
 	})
 }