Outbuilding approval rate in Hillingdon
Hillingdon approved 81.1% of outbuilding applications, based on 2,708 decisions analysed.
Last updated: September 2026
81.1%
outbuilding approval rate
2,708
Outbuilding decisions
2,197
Approved
511
Refused
77.9%
Hillingdon overall
Outbuilding applications are approved more often than the Hillingdon average (77.9%), suggesting the council is relatively receptive to these projects.
How outbuilding compares in Hillingdon
Outbuilding
81.1%
Hillingdon all applications
77.9%
Planning a outbuilding in Hillingdon?
81.1% get approved, but the odds vary by street. Your Full Planning Analysis shows exactly what gets approved and refused near your property.
✓ Your ward's outbuilding approval rate
✓ Nearest comparable outbuilding decisions
✓ Refusal triggers specific to your area
✓ PDF report for your architect
Free planning check for Hillingdon →
✓ Nearest comparable outbuilding decisions
✓ Refusal triggers specific to your area
✓ PDF report for your architect
Planning professional? PlanningLens runs refusal alerts and evidence packs for Hillingdon and any other published UK council — see the data services →
Other project types in Hillingdon
78.6%
81.9%
79.4%
71.9%
84.2%
83.8%
81.4%
66.4%
76.9%
73.7%
82.6%
74.3%
85.6%
57.7%
42.0%