what happens if I undercalculate what I owe

[lemrac]

hi guys,

What happens if in a pay and file I undercalculate what I owe? Am I better to overcalculate [ I'm assuming i'd get a rebate]

thank you

 

[Graham_07]

In P & F for 2009 if you pay less than either
100% pf previous year ( adjusted for Income Levy ) or
90% of ultimate current year
then you may be liable to interest.

If your payment exceeds the ultimate liability for the year Revenue will refund the excess.