Key:ref

ref
Description
Used for reference numbers or codes. Common for roads, highway exits, routes, etc.
Group: References
Used on these elements
Incompatible with
noref=*
Status: de facto
Tools for this tag
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Wikidata
Q1334113

"ref" stands for "reference" and is used for reference numbers or codes. Common for roads, highway exits, routes, etc. It is also used for shops and amenities that are numbered officially as part of a retail brand or network respectively.

This key and variations are frequently used to avoid the use of relations.

Key variations

• ref=*
• int_ref=* - international reference numbers or codes
• nat_ref=* - national reference numbers or codes
• reg_ref=* - regional reference numbers or codes
• loc_ref=* - local reference numbers or codes
• old_ref=* - old reference numbers or codes (usually replaced with another)
• unsigned_ref=* - reference number of code that is generally not signed on the route
• prow_ref=* - Public right of way reference (England and Wales only)

For cycle routes:

• ncn_ref=* - national cycle network reference
• rcn_ref=* - regional cycle network reference
• lcn_ref=* - local cycle network reference

There is wide use of ref:* as a namespace prefix, and since 2011 the use of a country code ref:FR:*, etc. where keys are clearly country-specific (see France/Liste des références nationales). A selection of frequently used variations are :

key	used on	description	see also	taginfo count (12 March 2021)
ref:bag=*		Id of Dutch buildings	BAGimport	10,470,051
ref:bic=*	heritage=*	identifiers for (Spain) Bien de Interés Cultural (BIC)	Bienes culturales protegidos by the Spanish Government.	688
ref:BLfD=*	heritage=*	Bayerisches Landesamt für Denkmalpflege (Germany, Bavaria)		6,943
ref:GB:cadw=*	heritage:operator=Cadw	id in Cadw's database of scheduled monuments and listed buildings in Wales, United Kingdom
ref:cadw=*	heritage:operator=cadw	deprecated please use ref:GB:cadw : id in Cadw's database of scheduled monuments and listed buildings in Wales, United Kingdom		825
ref:GB:nhle=*	heritage:operator=Historic England	id in National Heritage List for England as maintained by Historic England for England, United Kingdom	HE_ref=*
ref:GB:hs=*	heritage:operator=Historic Environment Scotland	id in the Historic Environment Scotland database of scheduled monuments and listed buildings in Scotland, United Kingdom
ref:GB:niea=*	heritage:operator=Northern Ireland Environment Agency	id in the Northern Ireland Environment Agency database of scheduled monuments and listed buildings in Northern Ireland, United Kingdom
ref:ctb=*	highway=bus_stop	Signposted on Citybus & NWFB bus stops (Hong Kong)		1,785
ref:De_Lijn=*	bus_stop/platform node, route, route_master	signposted on bus/tram stops in and around Flanders, Belgium	WikiProject_Belgium/De_Lijndata	38,114
ref:dhis2=*	boundary=health relation and health infrastructures	DHIS2 unique ID, used in +60 countries	Congo-Kinshasa/Zones_de_santé/Workflow	560
ref:doc=*	tourism=wilderness_hut	Shelters/Huts from the Department of Conservation (New Zealand)	Department of Conservation	977
ref:fgkz=*‡	Relation:waterway	FGKZ reference ID (Germany)		11,366
ref:GB:uprn=*	building=house, building=commercial, etc.	Unique Property Reference Number (Great Britain)		12,415
ref:GB:usrn=*	roads	Unique Street Reference Number (Great Britain)		3,644
ref:gnbc=*‡	Relation:waterway, Relation:boundary, place=*, others	GNBC reference ID (Canada)	About the Canadian Geographical Names Database	938
ref:gnis=*‡	Relation:waterway, Relation:boundary, place=*, others	GNIS reference ID (United States)		637
ref:harbour=*	landuse=industrial	Number of company in harbour on road signage, used e.g. in the Nederlands		41
ref:IFOPT=*	highway=bus_stop/public_transport=platform node	international identifier for bus stops and platforms		165,721
ref:industrial=*	landuse=industrial	Number of company in industrial area on road signage, used e.g. in the Nederlands		76
ref:INSEE=*	admin_level=*	INSEE code of the French communes		48,233
ref:isil=*	amenity=library	International Standard Identifier for Libraries		3,300
ref:IUCN=*	boundary=protected_area	International Union for the Conservation of Nature protected area category		197
ref:kmb=*	highway=bus_stop	Signposted on KMB & LW bus stops (Hong Kong)		3,810
ref:linz:address_id=*	addr:street=*	New Zealand street addresses	LINZ	2,057,602
ref:linz:building_id=*	building=yes	Imported buildings in New Zealand	LINZ	294,502
ref:linz:pastoral_lease_id=*	landuse=farmland	Agricultural stations in New Zealand	LINZ	57
ref:linz:topo50_id=*	*	Many different imported features in New Zealand/Antarctica/Polynesia	LINZ	69,348
ref:linz:hydrographic_id=*	seamark:type=*	Hydrographic/maritime features in New Zealand/Antarctica/Polynesia	LINZ	1
ref:mhs=*	heritage=*	id in the French database Mérimée of historic monuments		37,032
ref:MMM=*	highway=* or emergency=defibrillator or attraction=animal	object ID used by Montpellier Méditerranée Métropole, a french local authority	Montpellier#Utilisation_du_tag_ref:MMM	579
ref:NBd=*	junction=yes or traffic_sign=*	Reference number of the Dutch Nationale Bewegwijzeringsdienst (NBd)		104
ref:nid=*	heritage=*	id in Narodowy Instytut Dziedzictwa historic monuments		12,870
ref:nrhp=*	heritage=*	identifiers for (United States) National Register of Historic Places (NRHP) records 22	NRHP advanced search	5,337
ref:rce=*	heritage=*	Id in Dutch Rijksdienst voor het Cultureel Erfgoed		5,323
ref:regine=*‡	Relation:waterway	REGINE reference ID (Norway)		4
ref:RS:nkd=* heritage:RS:criteria=*	heritage=*	Immovable cultural property of Serbia	Key:heritage#Serbia http://editor.osmsrbija.iz.rs/nkd/ https://openstreetmap.rs/unos-nepokretnih-kulturnih-dobara-na-mapu-srbije/	825
ref:RS:naselje=* ref:RS:opstina=* ref:RS:grad=* ref:RS:okrug=* ref:RS:pokrajina=*	boundary=administrative admin_level=*	Offical designations for administrative regions in Serbia	https://openstreetmap.rs/kartografisanje-administrativnih-granica-na-mapi-srbije/	4 720 145 28 25 2
ref:RS:ulica=*	highway=*	Offical designations for streets in Serbia		3,832
ref:ruian=* ref:ruian:addr=* ref:ruian:building=*	building=*, addr=*	RUIAN building or address reference ID (Czech republic)		555,363 2,339,861 3,564,721
ref:sandre=*	river	ref of the French Sandre agency	WikiProject France/Cours d'eau	78,511
ref:svhl=*		station-keys of Lübecker Stadtverkehr (Germany)	Lübeck/Importe	2,475
ref:whc=*	heritage=*	id of the Unesco World Heritage		1,790
ref:TECB=*	bus_stop/platform node, route, route_master	signposted on bus stops in and around Brabant-Wallon, Wallonia, Belgium	TEC data import	3,577
ref:TECC=*	bus_stop/platform node, route, route_master	signposted on bus stops in and around Charleroi, Wallonia, Belgium	TEC data import	3,348
ref:TECH=*	bus_stop/platform node, route, route_master	signposted on bus stops in and around Hainaut, Wallonia, Belgium	TEC data import	5,486
ref:TECL=*	bus_stop/platform node, route, route_master	signposted on bus stops in and around Liège-Verviers, Wallonia, Belgium	TEC data import	9,300
ref:TECN=*	bus_stop/platform node, route, route_master	signposted on bus stops in and around Namur, Wallonia, Belgium	TEC data import	5,850
ref:TECX=*	bus_stop/platform node, route, route_master	signposted on bus stops in and around Luxembourg (province), Wallonia, Belgium	TEC data import	5,850
ref:UrbIS=*	building=* addr=*	Reference Key of Urbis Database for addresses in Brussels	Brussels#CIRB_UrbIS	289,991
ref:usrn=*		Unique Street Reference Number - a primary key use by the National Address Gazeteer in the UK	National Address Gazeteer	66,780
ref:VHAG=*	waterway=*	reference codenr. of waterways in Flanders,Belgium	Vlaamse Hydrografische Atlas	1,442
ref:hmdb=*	memorial=plaque	Reference ID for a historical marker or memorial plaque registered in the Historical Markers Database (HMdb)	Historical Marker Database
ref:thc=*	memorial=plaque	Reference ID for a historical marker or memorial plaque registered in the Texas Historical Commission Database	THC database (aka Atlas)
ref:pmmcr=*	*	identifiers used by Municipio de Marechal Cândido Rondon, a local government from Parana - Brazil.

‡ These keys are specifically encouraged for use by JOSM Waterway relation presets. Depending on the scope of the reference system, they may have uses in other key/tag schemas as well.

Core values

None

User defined values

Any valid syntax value

Examples on relations

States and provinces are often tagged with a postal abbreviation in ref. For example:

• ref=CA The state of California (type=boundary, admin_level=4, name=California - currently relation 165475)

On road routes, the ref is a bare number, relying on network=* to convey information about the road network:

• network=US:I ref=95 Interstate 95 in the United States

Similarly, on cycle and walking routes, the ref is a bare number and cycle_network=* indicates the route network:

• cycle_network=US:US ref=76 United States Bicycle Route 76

Bus routes use ref to label the bus route. For example:

• ref=23 Bus route 23. (type=route, route=bus, name=Shanklin>Newchurch>Newport - currently relation 312207)

Examples on ways

There are no global standards as to whether the refs include spaces, hyphens or other characters. At least when nationally consistent, tag what's on the ground. Some countries use spaces on the signs, others don't. In some countries the usage on the signs varies and guidelines are under discussion.

• ref=A 1 Default reference (German and French references with a space; e.g. A 1)
• int_ref=E 15 Internationally referenced as
• nat_ref=A 1 Nationally referenced as (German and French references with a space; e.g., A 1)
• reg_ref=A 1 Regionally referenced as (German and French references with a space; e.g., A 1)
• ncn_ref=54 The number reference for a National Cycle Network. See Cycle_routes
• ref=A 3;A 7 Default for more than one reference (German and French references with a space; e.g., A 1)

In the United States, some of the most popular ref formats do not correspond to what's on the ground, due to historical technical reasons. For example, Interstate highways are tagged e.g. ref=I 75 instead of ref=I-75, and some states use postal abbreviations instead of more ambiguous, human-readable prefixes such as "SR". However, this Sophox query demonstrates how a data consumer can automatically generate human-readable refs using the network=* tag on route relations.

It may seem redundant to tag route refs on both ways and relations, but do not remove a ref=* tag from a way just because the way is a member of corresponding route relations. Mainstream renderers and routers are still unable to infer refs from parent relations, so the way refs are needed for backwards compatibility. Moreover, in some localities, one cannot predict the order that concurrent routes are listed on a sign based on the route relations alone. A regional route may be listed before a national route if the national route only briefly joins the road before diverging. In these cases, ref=* on the way is the only way to indicate the signposted order along that way, since a way does not indicate an intrinsic order to the routes of which it is a member.

In runways of airports (aeroway=runway) this tag is used for the runway designator (for example "ref=02/20" or "ref=09L/27R").

Unsigned reference numbers (e.g. New York State Reference Route Numbers) that are not readily visible on the ground should be placed in unsigned_ref rather than ref.

Examples on nodes

A ref on a node generally means a highway exit when combined with highway=motorway_junction:

• ref=23 US Highway exits are often just a number
• ref=23B Sometimes exits have been split into A and B exits.

These refs can also be tagged on the adjoining highway=motorway_link way (or highway=trunk_link, highway=secondary_link, etc.) using junction:ref=*. In general, renderers understand ref=* on nodes, while routers understand junction:ref=* on ways.

ref is sometimes used on bus stops:

• ref=107309

ref is sometimes used to label an entrance into a large building or parking area. For example a shopping mall may have entrances A - L:

• ref=A

Special uses

• ref:svhl=* - station-keys of Lübecker Stadtverkehr (Germany) - details look at Lübeck/Importe
• ref:luebeck=* - internal reference for objects the area of Lübeck
• ref:bufa=* - 4-digit key of the local German tax and revenue offices (Bundesfinanzamtnummer)
• ref:vatin=CC12345678 - VAT identification number of companies, use CountryCode (e.g. IT for Italy) and the number
• official_ref=* - Used in cases where the official administrative reference for a road (or other feature) is not identical with the road signs (or other feature ref), e.g. because they are old, or because the administration doesn't have the money to install/update the signage.
• ref=xxxx - Used to mark official company store number assigned to a place. Example (ref=7872) CVS (You'll see a reference tag added to the building)
• ref:penndot=* - Used for internal state route designations of the Location Referencing System in Pennsylvania.

See also

• route_ref=* - route reference (number/code) cognizable on public transport stop signs
• local_ref=* - local reference/local platform
• junction:ref=* – motorway exit number
• ref:FR:*=*: WikiProject France/Liste des références nationales
• bridge:ref=*
• ref:US:EPA=*: United States EPA facilities registration codes

For United States road tagging

References

This is used to add reference information for an element.

LOADING TAG LIST... (If you do not see this tag list, you need to enable Javascript)

This table is a wiki template with a default description in English. Editable here.

Notes

• For highways shared by more than one route see Relations/Routes or Faq#What shall I do for roads that have multiple values for a tag?. Relations seem to be the preferred method for tagging this.
• If more than one reference is given, you are recommended to separate them with a semicolon and without a space character, because this is the widely established syntax in Germany and maybe other countries. But note, this syntax is being heavily discussed in Germany. A better approach might be to have a namespace and add the entity that has issued the ref, e.g. ref:foo=x ref:bar=y.
• Do not confuse this issue with the space that is present in some countries between the letter and the number in a reference itself.
• When a road has no number, leave this key unused; this makes sure that routing programs do not try to describe the road by a number.

Possible tagging mistakes

• refer=*

If you know places with this tag, verify if it could be tagged with another tag.
Automated edits are strongly discouraged unless you really know what you are doing!

• reference=*

If you know places with this tag, verify if it could be tagged with another tag.
Automated edits are strongly discouraged unless you really know what you are doing!