Society of Maritime Arbitrators
Resolving Maritime Disputes For Over 50 Years

Arbitrators in New York, in most cases, award interest to the prevailing party based on the Commercial Prime Rate that banks commonly charge their business customers. These rates change based on announcements of the Federal Reserve Board. Depending on the length of time that has passed before issuance of a final award in arbitration, the prime rate may have changed between the date of the claim and the issuance of the award.

As a service to our friends and Members we are pleased to provide, herein, a quick and accurate method for calculating interest at the Commercial Prime Rate.

By clicking on the link below you can navigate to a web page to calculate simple interest accumulated on a known principal amount over a period between two known dates.

Click here to bypass the instructions and go directly to the INTEREST CALCULATOR.

Use the drop down menus to select a starting Month, Day, and Year of the claim. Enter the awarded amount into the Claim Value box, avoiding dollar signs ($) and commas when entering the amount. Use the next set of drop down boxes to select the ending Month, Day, and Year. Click on the Calculate Interest button to see interest owed over each interest change period and a running total of all interest owed.

Our data base reflects the last change in interest rates that took effect on December 14, 2017 at 4.5%. If you know that there has been a subsequent rate change in the Commercial Prime Rate and we have not yet made the appropriate update to our data base, we would appreciate a reminder.

If you have problems using this service, or wish to comment, please e-mail our Technical Committee. The user of this Interest calculator should make their own check of the results. The SMA is not responsible for the consequence of any inaccuracy resulting from the use of this calculation device.

Click here to access the INTEREST CALCULATOR.

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