Proposal:Directional Prefix & Suffix Indication

From OpenStreetMap Wiki
Jump to navigation Jump to search
Directional Prefix & Suffix Indication
Proposal status: Abandoned (inactive)
Proposed by: Kevina
Tagging: name:prefix,name:suffix,name:full=*
Applies to: way
Definition: Tags to mark directionals which are more part of an address than the street name.

Draft started: 2010-08-09
RFC start: 2010-08-22


In many areas of the United States, street names have directional indicators to indicate what part of the city the road is in. They are generally requires when forming an address. Vid the kid, gave an excellent overview at For example (from his page) in the address:

  4242 S Champion Ave E

The 'S' is a directional prefix and the 'E' is the suffix and in:

  1337 Rainbow Dr SW

The 'SW' is a directional suffix (really a quadrant suffix).


In some areas the directionals are also considered part of the street names. In other areas the directionals are more considered part of the address. In the latter case the directional is almost always a prefix and are generally not in front on the street name on the street signs. If anywhere, they are in a smaller font, after the address starting number or range, further reinforcing the fact that they are address information, not part of the name. They are most likely present in the name of a road because of the TIGER import, as no distinction was made between prefixes which belong as part of the name and prefixes which are really address information.

This proposal is about separating out the directional prefix from the name when the prefix is really part of the address. It is also to prevent the lose of information as without a formal tag, some locals may remove the prefix without storing it in another tag. See changeset,

Suffixes are included for completeness, but I do not know of a situation when they should be used.


I propose new tags to record directionals which are more part of an address:

Assuming the name is stored in "name" the new tags shall be


If an alternative street name is stored in another tag than replace "name" with that tag, for example "alt_name:prefix".

If the directional prefix or suffix is not part of the name than the appropriate tag shall be used to indicate the need for a directional prefix in an address. It shall consist of the unabbreviated directional with the initial letter in capital, for example "North", "South", "Northwest", etc.

The full name can go in 'name:full" as an aid in name finder and the like. But this tag is essentially redundant so I am glad to make it optional.

If the full name is not provided the formation of an address shall be as follows:

  <number> <prefix if it exists> <name> <suffix if it exists>

Criteria for Prefixes

As already indicated, the prefix should only be separated out when it is considered more part of the address than of the street name. In general this means that North/South streets will have a prefix of East or West depending on if the address is to the East or West of the center or the grid, and conversely East/West streets will have a prefix of North or South.

The types of directionals (prefix and suffix) which should not be separated out are ones which identify a region of the city. In these cases there are often two roughly parallel streets with the same name. Also, all streets in a particular region will generally have the same directional indicators. A good example of this is Portland, OR.

In general the choice should be obvious if you are a local to the area. If you are not a local it is best to ask someone who is. If you are a local and you still can't decide ask yourself the following questions:

  1. When giving the intersection of any two streets in the city is it necessary to include the prefix or somehow indicate the directional? That is will dropping the prefix lead to an ambiguous situation that could possible identify more the one location? If so, they should definitely not be separated out.
  2. Is the prefix included on the signs? If not, than this is a good indication that they are not really important, and can most likely be separated out. If it is included, but in smaller letters, than you should base you decision on the other two criteria. If it is included before the name, in the same size font, than the prefixes should most likely be kept.
  3. When identifying a street (without given an address) to someone not familiar to the area will you (a local) include the prefix? Are they included in official documents like assessor's and tract maps? If not than they should probably be separated out.

If you still can't decide it is best to leave the prefixes in.


Salt Lake City

In Salt Lake City, the directional prefixes are: (1) Not needed when giving the intersection of two streets. In fact due to how streets are commonly named, including them will be downright confusing for example "East 200 South and South 300 East" (yes the street name is really East 200 South). (2) Not signed that way as I have yet to see a sign that includes the prefix. And (3) generally not used when identifying a street, thus the prefixes should be separated out:

Before After
name="East 200 South" name="200 South"
name:full="East 200 South"
name="West South Temple"
name="South Temple"
name:full="West South Temple"

Other Examples

Before After Notes
name="West Gay Street" name="Gay Street"
name:full="West Gay Street"
Columbus, OH
name="West Case Road" name="West Case Road" Columbus, OH.
Here "West" is really part of the street name
name="Southwest Takena" name="Southwest Takena" Portland, OR
Here "Southwest" is a directional prefix, but it specifies a region of the city, and does not pass any of the above tests. Thus it should be kept according to this proposal.
name="West North Bend Road" name="North Bend Road"
name:full="West North Bend Road"
way 30431954 in Cincinnati, OH
Here, "North Bend" refers to relation a village, not the northern part of "Bend", wherever that is.

Other Possible Uses

The :prefix and :suffix tags can also be used for non-directional parts of the street name that are considered more part of an address, than of the street name. I do not know of any such examples, but want to leave the tags open for such use.


This proposal is only about separating out the prefix (and possible the suffix) when they do not belong as part of the street name. Full breakout of the components of the street name is beyond the scope of the proposal.

Nevertheless, I want my proposal to be compatible with a full breakout, including the upcoming FGDC address standard (, Therefore here is what I propose. The :prefix and :postfix tags are reserved as outlined above. New tags shall be used for the directional prefix as specified in the standard, for example ":dir_prefix". The difference between the two tags is that ":prefix" should only be used when the prefix is not part of the name and ":dir_prefix" should always be used when the name has a directional prefix component. When forming an address either the tags used in this proposal or the tags used in the address can be used and the results should be identical.

If you wish to propose a full breakout, please create a new proposal. Please limit the scope of discussion to making this proposal compatible with a possible future breakout.

The ":prefix" and ":suffix" tag are unabbreviated to make them compatible with the upcoming FGDC address standard and also the meaning of "name:prefix=East" is more self explanatory than "name:prefix=E". I do not have a strong viewpoint in the manor though, and can probably easily be convinced to use the standard directional abbreviations.

Current Use

The "name:prefix" and "name:full" is in use in the Salt Lake City, UT, USA area to good effect. But I can very easily change the tags to something else if a different convention is agreed upon.