Adjust the units you express the period in to days (or half months or weeks, whatever your requirements are).
Of course you'll have to adjust the interest rates accordingly.

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Kind regards,

Niek Otten
Microsoft MVP - Excel

"Woody13" wrote in message ...
| I'm want to know, for an equal amortizing loan, the interest amount for each
| period. However, the first period is a fractional period. It starts today
| and calculated until the beginning of Sept. I'm not sure how to use the PMT
| and IPMT functions for fractional periods. thx