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=*
Wikidata
Q1334113
Status: de facto
Tools for this tag
taginfo · CH · CZ · FR · GB · HU · IE · IN · JP · PL overpass-turbo

"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=*
• nat_ref=*
• reg_ref=*
• loc_ref=*
• old_ref=*
• unsigned_ref=*

For cycle routes:

• ncn_ref=*
• rcn_ref=*
• lcn_ref=*

There is a wide use of ref:* as a namespace prefix. A selection of frequently used variations is listed here :

key	used on	description	see also	taginfo count (25 June 2018)
ref:bag=*		Id of Dutch buildings	BAGimport	10112655
ref:bic=*	heritage=*	identifiers for (Spain) Bien de Interés Cultural (BIC)	Bienes culturales protegidos by the Spanish Government.	527
ref:cadw=*	heritage:operator=cadw	id in Cadw's database of scheduled monuments and listed buildings in Wales, United Kingdom
ref:ctb=*	highway=bus_stop	Signposted on Citybus & NWFB bus stops		1651
ref:De_Lijn=*	bus_stop/platform node, route, route_master	signposted on bus/tram stops in and around Flanders, Belgium	WikiProject_Belgium/De_Lijndata	38318
ref:dhis2=*	boundary=health relation and health infrastructures	DHIS2 unique ID, used in +60 countries	Congo-Kinshasa/Zones_de_santé/Workflow
ref:fgkz=*‡	Relation:waterway	FGKZ reference ID (Germany)		9927
ref:gnbc=*‡	Relation:waterway, Relation:boundary, place=*, others	GNBC reference ID (Canada)	About the Canadian Geographical Names Database	52
ref:gnis=*‡	Relation:waterway, Relation:boundary, place=*, others	GNIS reference ID (United States)		18
ref:harbour=*	landuse=industrial	Number of company in harbour on road signage, used e.g. in the Nederlands
ref:IFOPT=*	highway=bus_stop/public_transport=platform node	international identifier for bus stops and platforms		114301 count from 2019-04-20
ref:industrial=*	landuse=industrial	Number of company in industrial area on road signage, used e.g. in the Nederlands
ref:INSEE=*	admin_level=*	INSEE code of the French communes		77693
ref:isil=*	amenity=library	International Standard Identifier for Libraries		1539
ref:kmb=*	highway=bus_stop	Signposted on KMB & LW bus stops		3199
ref:mhs=*	heritage=*	id in the French database Mérimée of historic monuments		34120
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	278
ref:NBd=*	junction=yes or traffic_sign=*	Reference number of the Dutch Nationale Bewegwijzeringsdienst (NBd)		99
ref:nid=*	heritage=*	id in Narodowy Instytut Dziedzictwa historic monuments		10634
ref:nrhp=*	heritage=*	identifiers for (United States) National Register of Historic Places (NRHP) records 22	NRHP advanced search	3626
ref:rce=*	heritage=*	Id in Dutch Rijksdienst voor het Cultureel Erfgoed		4528
ref:regine=*‡	Relation:waterway	REGINE reference ID (Norway)		2
ref:ruian=* ref:ruian:addr=* ref:ruian:building=*	building=*, addr=*	RUIAN building or address reference ID (Czech republic)		565550 2275524 2862196
ref:sandre=*	river	ref of the French Sandre agency	WikiProject France/Cours d'eau	52151
ref:svhl=*		station-keys of Lübecker Stadtverkehr (Germany)	Lübeck/Importe	2322
ref:whc=*	heritage=*	id of the Unesco World Heritage		1464
ref:TECB=*	bus_stop/platform node, route, route_master	signposted on bus stops in and around Brabant-Wallon, Wallonia, Belgium	TEC data import	3602
ref:TECC=*	bus_stop/platform node, route, route_master	signposted on bus stops in and around Charleroi, Wallonia, Belgium	TEC data import	3398
ref:TECH=*	bus_stop/platform node, route, route_master	signposted on bus stops in and around Hainaut, Wallonia, Belgium	TEC data import	5638
ref:TECL=*	bus_stop/platform node, route, route_master	signposted on bus stops in and around Liège-Verviers, Wallonia, Belgium	TEC data import	9316
ref:TECN=*	bus_stop/platform node, route, route_master	signposted on bus stops in and around Namur, Wallonia, Belgium	TEC data import	5357
ref:TECX=*	bus_stop/platform node, route, route_master	signposted on bus stops in and around Luxembourg (province), Wallonia, Belgium	TEC data import	5848
ref:UrbIS=*	building=* addr=*	Reference Key of Urbis Database for addresses in Brussels	Brussels#CIRB_UrbIS	292732
ref:usrn=*		Unique Street Reference Number - a primary key use by the National Address Gazeteer in the UK	National Address Gazeteer	66847
ref:VHAG=*	waterway=*	reference codenr. of waterways in Flanders,Belgium	Vlaamse Hydrografische Atlas

‡ 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.

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 change the signs.
• 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

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.