It's normal to have money saved up ahead of time for paying bills that are due.
他に使える言い方を紹介したいと思います:
「支払い期日に向けて積立てていくのが普通でしょう」
It's normal to have money saved up ahead of time for paying bills that are due.
it's normal (to)... = ~のが普通
it's usual toやit's regular toと同じ意味です。
have money saved up = お金を貯めること・お金を用意すること
save up moneyという言い方も使えます。
ahead of time = 前もって
ahead of timeはin advanceと同じ意味です。
for paying bills that are due = 支払期限が来る手形のために