Key:zone:parking

zone:parking=* is a parking-specific key with two different uses.

Residential parking zones

This feature has been labeled as deprecated. The recommended replacement is: zone=* for amenity=parking and parking:side:zone for street parking.
The reason is documented in Deprecated features. You are still free to continue to use or interpret this tag as you see fit since OpenStreetMap does not have “banned features”.
Under no circumstances should you (semi-)automatically change “deprecated” tags to something else in the database on a large scale without conforming to the automated edits code of conduct. Any such change will be reverted.

zone:parking=* is an old way to denote fee exemptions for residents of a certain zone, possibly synonymous to zone:parking=*. After a revision of street parking, this use has been deemed deprecated.

Parking restriction zones

Another use of zone:parking=* is for to denote a default parking restriction of streets. In these streets, the parking restrictions are implied beyond the boundary of the zone instead of requiring the constant placement of parking restriction signage akin to zone:maxspeed=* for maxspeed=*.

The format for the values is <country-code>:<parking-restriction>.

Country codes should be upper case.