Joint Statement by Ordnance Survey Ireland and the Property Registration Authority of Ireland

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The Property Registration Authority (Land Registry) and Ordnance Survey Ireland (OSI) enjoy a very close working relationship. The Land Registry utilises Ordnance Survey Ireland’s topographic mapping to cross-reference and associate their boundary information. This forms the basis of all Land Registry digital map data.

Ordnance Survey Ireland and Land Registry have compiled the information below to help customers understand their respective roles.

Ordnance Survey Ireland’s Role

Ordnance Survey Ireland is the national mapping agency of Ireland. It is the State Agency  responsible for the official, definitive surveying and topographic mapping of the Republic of Ireland. As this mapping is topographic, it only represents the physical features on the ground at the time of survey. The features shown must fall within the specification for the survey scale and within agreed accuracy tolerances.

OSI maps never indicate legal property boundaries, nor do they show ownership of physical features. Although some property boundaries may be coincident with surveyed map features, no assumptions should be made in these instances and consequently it is not possible to identify the position of a legal property boundary from an OSI map.

OSI has a continuous mapping revision programme for the whole of the Republic of Ireland. Changes that have occurred on the ground since the property was registered may result in differences between later OSI map editions and the mapping used by the Land Registry.

Contact Ordnance Survey  Ireland
Ordnance Survey Ireland is unable to answer questions regarding legal property boundaries or interpret the mapping in your title plan. However, if you have questions regarding their mapping you can:

  • E-mail
  • Call their LoCall number on 1890 67 46 27
  • Or write to:

Customer Service Centre,
Ordnance Survey Ireland,
Phoenix Park,
Dublin 8.

Property Registration Authority

The main functions of the PRA are to manage and control the Registry of Deeds and the Land Registry and to promote and extend the registration of ownership of land.

Land Registry’s Role
The Land Registry was established in 1892 to provide a comprehensive and secure system of land registration. When property title is registered in the Land Registry the deeds are filed in the Registry and all relevant particulars concerning the property and its ownership are entered on folios which form the registers maintained in the Land Registry. In conjunction with folios the Land Registry also maintains Land Registry maps. Both folios and maps are maintained in electronic form. Land Registry maps (digital vector data) are based on Irish Transverse Mercator (ITM) coordinate reference system topographic maps that are supplied to the Registry in digital vector form by Ordnance Survey Ireland. Published scales are 1/5,000 rural, 1/2,500 urban/rural, 1/1,000 urban. The Land Registry represents the extent of all registered land by reference to OSI topographic map data. Where a boundary of the land is not defined by a physical feature on the OSI map, the Land Registry digitises it from either the electronic or paper map(s) lodged by applicants for registration purposes. The word “boundary” has no special meaning in law but in land ownership it is understood in two ways:

The Physical Boundary
The Land Registry identifies properties not boundaries and never shows ownership of individual boundary structures such as walls, fences and hedges etc. It should also be noted that deeds rarely deal with such matters.

Non-conclusive Boundary System
The boundary system adopted by the Land Registry under the Registration of Title Act, 1964 is known as a non-conclusive boundary system. The non-conclusive provision dispenses with the need for determining the exact location of title boundaries when defining the extent of registered properties and the ownership of the physical features which mark the limits of a property is left undetermined. In the case of boundaries located within buildings, the exact line or plane of the title boundary is also left undetermined.

The non-conclusive boundary system will not indicate whether a title boundary includes a hedge or a wall and ditch or runs along the centre of a wall or fence or runs along its inner or outer face or how far it runs within or without it or whether or not the land registered includes the whole or any portion of an adjoining road or stream. However, the location of the physical features within which the title boundary lies or the points between which an undefined title boundary runs must be accurately defined by the applicant on the map lodged for registration within the limitations of the scale of the application map.

Official copies of the Registry Map can be obtained by ordering any of the following:-

  • Special Registration Map
  • Title Plan
  • Official Map Search

Each of the above map products are generated from the Land Registry digital vector map and includes some surrounding OSI topographic detail. Official copies of Land Registry maps are subject to the limitations of scale and survey accuracy of both:

  • OSI maps on which they are based
  • The application maps lodged for registration purposes

Where boundaries have been transferred to a larger scale or to a different map series, whether on paper or in a digital environment, measurements must not be expected to give a degree of accuracy greater than that of the smaller scale or older map series. Since the commencement of land registration in 1892, almost all registrations were recorded by reference to the topographic detail shown on OSI published map scales. OSI Cassini/County Series and Irish Grid published scales in the paper system were 1/10,560, 1/2,500 1/1,000 and some urban areas were published at 1/1,250 and 1/1,056, (both 1/1,250 and 1/1,056 were enlarged by OSI from 1/2,500 mapping). Accuracy of the Land Registry’s boundary data is, accordingly, limited to the survey accuracy and scale of the source map originally lodged and upon which registration was based. The Land Registry is unable to tell you precisely where a property boundary is located.

Questions about Land Registration
Land Registry publishes a number of public guides about land registration which can be viewed or downloaded from its website at or obtained free of charge from any Land Registry office. The website also has a ‘frequently asked questions’ section.