How much land in Blanchardstown, Castleknock and Ongar is on the RZLT map?
1,104 ha of land in Blanchardstown, Castleknock and Ongar is on the Residential Zoned Land Tax map, across 1,093 parcels (2027 draft RZLT map), as of 25 Sep 2026. 991 ha of it has no live permission for 10 or more homes. The tax is 3% of market value a year, collected by Revenue on maps the councils make.
From public registers, checked 25 Sep 2026. Updated nightly.
- 1,104 haOn the map
- 1,093Parcels
- 991 haNo live permission
The largest RZLT parcels in Blanchardstown, Castleknock and Ongar
Land in Blanchardstown-Mulhuddart
Blanchardstown-Mulhuddart · Fingal · 22.75 ha · source
On the RZLT map (3% land tax)
22.8 ha, On the 2027 draft RZLT map
Land in Castleknock
Castleknock · Fingal · 14.21 ha · source
On the RZLT map (3% land tax)
14.2 ha, On the 2027 draft RZLT map
Land in Castleknock
Castleknock · Fingal · 12.79 ha · source
On the RZLT map (3% land tax)
12.8 ha, On the 2027 draft RZLT map
Land in Castleknock
Castleknock · Fingal · 10.13 ha · source
On the RZLT map (3% land tax)
10.1 ha, On the 2027 draft RZLT map
Land in Blanchardstown-Mulhuddart
Blanchardstown-Mulhuddart · Fingal · 9.39 ha · source
On the RZLT map (3% land tax)
9.4 ha, On the 2027 draft RZLT map
Land in Castleknock
Castleknock · Fingal · 8.58 ha · source
On the RZLT map (3% land tax)
8.6 ha, On the 2027 draft RZLT map
Land in Castleknock
Castleknock · Fingal · 8.55 ha · source
On the RZLT map (3% land tax)
8.6 ha, On the 2027 draft RZLT map
Land in Castleknock
Castleknock · Fingal · 8.52 ha · source
On the RZLT map (3% land tax)
8.5 ha, On the 2027 draft RZLT map
Land in Ongar
Ongar · Fingal · 8.4 ha · source
On the RZLT map (3% land tax)
8.4 ha, On the 2027 draft RZLT map
Land in Castleknock
Castleknock · Fingal · 8.06 ha · source
On the RZLT map (3% land tax)
8.1 ha, On the 2027 draft RZLT map
Land in Blanchardstown-Mulhuddart
Blanchardstown-Mulhuddart · Fingal · 7.84 ha · source
On the RZLT map (3% land tax)
7.8 ha, On the 2027 draft RZLT map
Land in Ongar
Ongar · Fingal · 7.4 ha · source
On the RZLT map (3% land tax)
7.4 ha, On the 2027 draft RZLT map
Land in Ongar
Ongar · Fingal · 7.32 ha · source
On the RZLT map (3% land tax)
7.3 ha, On the 2027 draft RZLT map
Land in Castleknock
Castleknock · Fingal · 7.27 ha · source
On the RZLT map (3% land tax)
7.3 ha, On the 2027 draft RZLT map
Land in Castleknock
Castleknock · Fingal · 7.22 ha · source
On the RZLT map (3% land tax)
7.2 ha, On the 2027 draft RZLT map
Land in Castleknock
Castleknock · Fingal · 6.71 ha · source
On the RZLT map (3% land tax)
6.7 ha, On the 2027 draft RZLT map
Land in Ongar
Ongar · Fingal · 6.58 ha · source
On the RZLT map (3% land tax)
6.6 ha, On the 2027 draft RZLT map
Land in Castleknock
Castleknock · Fingal · 6.44 ha · source
On the RZLT map (3% land tax)
6.4 ha, On the 2027 draft RZLT map
Land in Castleknock
Castleknock · Fingal · 6.1 ha · source
On the RZLT map (3% land tax)
6.1 ha, On the 2027 draft RZLT map
Land in Castleknock
Castleknock · Fingal · 5.72 ha · source
On the RZLT map (3% land tax)
5.7 ha, On the 2027 draft RZLT map
Land in Castleknock
Castleknock · Fingal · 5.52 ha · source
On the RZLT map (3% land tax)
5.5 ha, On the 2027 draft RZLT map
Land in Castleknock
Castleknock · Fingal · 5.35 ha · source
On the RZLT map (3% land tax)
5.3 ha, On the 2027 draft RZLT map
Land in Castleknock
Castleknock · Fingal · 5.3 ha · source
On the RZLT map (3% land tax)
5.3 ha, On the 2027 draft RZLT map
Land in Blanchardstown-Mulhuddart
Blanchardstown-Mulhuddart · Fingal · 5.3 ha · source
On the RZLT map (3% land tax)
5.3 ha, On the 2027 draft RZLT map
Land in Castleknock
Castleknock · Fingal · 5.26 ha · source
On the RZLT map (3% land tax)
5.3 ha, On the 2027 draft RZLT map
Showing 25 of 1,093. See them all →
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More about Blanchardstown, Castleknock and Ongar
- Is there development land for sale in Blanchardstown, Castleknock and Ongar?
- Buildable found 62 sites in Blanchardstown, Castleknock and Ongar with a public sign they could come to market, as of 25 Sep 2026: 26 council sites proposed for sale, 2 sites with planning permission running out or recently expired, 2 derelict sites on the register and 41 stalled builds. These come from public registers, not agents' listings, so many are not advertised yet.
- How many development sites are there in Blanchardstown, Castleknock and Ongar?
- Buildable tracks 1,663 development sites in Blanchardstown, Castleknock and Ongar, as of 25 Sep 2026: every site with a public reason it could be built on or sold, from the councils' and national registers. They include 9 permitted schemes not started, 13 derelict sites, 32 council land sales and 41 stalled builds.
- What are the largest development sites in Blanchardstown, Castleknock and Ongar?
- 484 development sites in Blanchardstown, Castleknock and Ongar are a hectare or larger, as of 25 Sep 2026. The largest is public land in Blanchardstown-Mulhuddart, at 38.9 ha (publicly owned land).
- How much zoned land in Blanchardstown, Castleknock and Ongar has no planning permission?
- 991 ha in Blanchardstown, Castleknock and Ongar is zoned for housing, on the RZLT map and has no live permission for 10 or more homes: 1,038 parcels, as of 25 Sep 2026. Land on the map is liable for the Residential Zoned Land Tax of 3% of market value a year.
Data as of 25 Sep 2026. Sources: Council Residential Zoned Land Tax maps.
Cite this: How much land in Blanchardstown, Castleknock and Ongar is on the RZLT map? Buildable, data as of 25 Sep 2026. https://buildable.ie/q/rzlt-land-dublin-15
Facts from public registers, not advice. Every question · How it works