Exit numbers on Wisconsin freeways help orient drivers to
their location. Wisconsin uses a reference location approach to
identify exit numbers, which means the exit numbers relate to the
mile reference sign, or mile marker, at that location.
used on freeways begin at 0 on the west or south termini of the
route within Wisconsin and progress to the east or north. On
freeways where more than one numbered route exists on the same
roadway, one highway will be used to establish the mile reference.
Generally the lower numbered Interstate highway takes precedence in
the numbering scheme, but that may vary depending on the history of
the route, or other factors.
When more than one exit occurs within the same mile, the first
exit will be identified with the number and the letter A, the second
exit B, and so on. Each exit will have an exit sign, with the exit
number, at the point where the ramp diverges from the freeway.
Exit numbers are also used on the top of exit direction signs.
When exit numbers appear on top of exit direction signs or on top of
interchange guide signs, the placement of the exit number plaque
will confirm whether the exit is a right exit or a left exit.
The Exit 4A sign is located on the
left-hand side of the interchange guide sign, indicating the
exit uses the left-hand lane.
Likewise, the Exit 240 sign is
positioned in the center of the interchange guide sign,
indicating travelers should use the center lanes to enter WIS
The Exit 142A sign is positioned on the
right-hand side of the interchange guide sign. Therefore this
exit will use the right-hand lane.
Exit numbers and reference mile numbers are useful information
when reporting highway incidents.