Let's Start With The Top Part Of The Fraction
Those fractions on the top of checks tell us a lot about the check itself. And compared to the MICR number on the bottom, can provide verification of the numbers being correct-IF you know how to read them.
The top set of numbers on the check is the fractional form of the routing number.
The prefix number tells us the general location of the institution named on the check.
The rules for prefix numbers (the numbers on the top/left of the fraction) are listed below.
There are twelve Federal Reserve Districts. Each institution (whether it be savings and loan, savings bank, thrift, commercial bank or credit union) in each of the twelve districts, has its own number. That appears on the top/right of the fraction.
Using this information, if the fraction at the top of the check was 3-2/310 we would know that institution number 2 in the third Federal Reserve District (310) is located in a major banking city. If the fraction was 50-77/213 we would know that institution number 77 is located in the state of New York and is serviced by the second Federal Reserve District (the 213 tells us that).
90-3911/1222 would be institution number 3911 in California, serviced by the twelfth (1222) Federal Reserve District. (We'll talk about those Federal Reserve numbers in a later issue of BANKERS' HOTLINE.)
Take a closer look at some of the checks you work with today. The Federal Bureau of Investigation estimates that 80% of all counterfeit checks bear incorrect transit numbers. It's a good number to verify.
Copyright © 1990 Bankers' Hotline. Originally appeared in Bankers' Hotline, Vol. 1, No. 4, 4/90
First published on 04/01/1990