Brian Dunning's FileMaker Custom Functions

Monthly Payment ( Loan Amount ; APR ; Term ; Days To First Payment

Calculate monthly payments with odd-days interest.

  Average rating: 3.9 (44 votes) Log in to vote

Michael Myett   Michael Myett
FileMaker Apps

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  Sample input:
Monthly Payment ( 15000 ; .07 ; 60 ; 45 )
  Sample output:

  Function definition: (Copy & paste into FileMaker's Edit Custom Function window)

FileMakers PMT function calculates monthly payments based on the first payment being 30-days from loan inception. This period of time can actually be up to 45-days, for example, to adjust the payment date to a comfortable time of the month for your customer.
This custom function will accurately calculate the correct monthly payment, including odd-days interest, for any simple interest loan. Try using this function and compare the results to FileMakers standard PMT function; you'll see there is a slight difference in the payments.



achyoot sapkota   achyoot sapkota, Kathmandu
Sep 19, 2011
How can i use this function . I have no idea. would u please kindely expain
Gary Campla   Gary Campla, Jacksonville, FL
Dec 2, 2012
This Function was almost perfect, now that it's Truncated it works flawless and it will match any Financial Institutions using "Days to First Payment". Congratulations Michael Myett, you did great.

Truncate ( Let ( [ Amount Financed = Financed + If ( Days Before First Pmt ≠ 30 ; ((( Percentage Rate / 1200 ) * ( Days Before First Pmt -30 )) / 30 ) * Financed ; 0 ) ; IntRate = Percentage Rate / 1200 ] ; PMT ( Amount Financed ; IntRate ; Terms )) ; 2 )

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Note: these functions are not guaranteed or supported by Please contact the individual developer with any questions or problems.

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