What is the average rear extension approval rate in the UK?

Across 176 councils and 493,050 decisions, the average approval rate is 90.7%. But rates vary enormously by council and location.

Which council has the highest rear extension approval rate?

Mid Devon at 100.0% based on 327 decisions.

How many rear extension applications get refused?

Of 493,050 decisions nationally, 69,267 were refused. That is roughly 1 in 7 applications.

Rear Extension — What Are Your Chances? UK Approval Rates (May 2026)

10 Best Councils for Rear Extensions

These councils approve rear extension applications at the highest rate. But remember — a high council average can hide wards where refusal rates are double the headline figure.

#	Council	Decisions	Refused	Rate
1	Mid Devon	327	0	100.0%
2	Fareham	479	1	99.8%
3	Hinckley & Bosworth	807	5	99.4%
4	South Lanarkshire	4,892	28	99.4%
5	West Lancashire	837	7	99.2%
6	Carlisle	517	5	99.0%
7	Gosport	483	5	99.0%
8	Stockton-on-Tees	301	3	99.0%
9	Mansfield	634	7	98.9%
10	Broadland	650	8	98.8%

Found your council? See what's happening at street level →

10 Hardest Councils for Rear Extensions

These councils refuse rear extensions at the highest rate. If you're planning a rear extension in one of these areas, checking your local data first could save you thousands in wasted fees.

#	Council	Decisions	Refused	Rate
1	Cardiff	265	98	63.0%
2	Greenwich	5,373	1,812	66.3%
3	Brent	12,106	3,314	72.6%
4	Barking & Dagenham	2,715	745	72.6%
5	Kingston	7,226	1,807	75.0%
6	Waltham Forest	7,930	1,959	75.3%
7	Lewisham	4,494	1,104	75.4%
8	Barnet	17,196	4,145	75.9%
9	Hillingdon	9,930	2,229	77.6%
10	Thurrock	3,518	776	77.9%

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All 176 Councils Ranked for Rear Extensions

#	Council	Decisions	Approved	Refused	Rate
1	Mid Devon	327	327	0	100.0%
2	Fareham	479	478	1	99.8%
3	Hinckley & Bosworth	807	802	5	99.4%
4	South Lanarkshire	4,892	4,864	28	99.4%
5	West Lancashire	837	830	7	99.2%
6	Carlisle	517	512	5	99.0%
7	Gosport	483	478	5	99.0%
8	Stockton-on-Tees	301	298	3	99.0%
9	Mansfield	634	627	7	98.9%
10	Broadland	650	642	8	98.8%
11	Harlow	423	418	5	98.8%
12	Torridge	316	312	4	98.7%
13	South Norfolk	566	558	8	98.6%
14	Bromsgrove & Redditch	390	384	6	98.5%
15	Stirling	481	474	7	98.5%
16	North East Lincolnshire	374	368	6	98.4%
17	Lincoln	941	925	16	98.3%
18	South Ribble	984	966	18	98.2%
19	Cheltenham	2,399	2,351	48	98.0%
20	Blaby	709	694	15	97.9%
21	Cornwall	323	316	7	97.8%
22	County Durham	1,451	1,419	32	97.8%
23	Winchester	898	878	20	97.8%
24	Arun	300	293	7	97.7%
25	Tamworth	1,117	1,091	26	97.7%
26	Knowsley	1,385	1,348	37	97.3%
27	Plymouth	1,196	1,164	32	97.3%
28	Rushmoor	891	867	24	97.3%
29	South Tyneside	681	662	19	97.2%
30	Melton	329	319	10	97.0%
31	Rugby	1,057	1,025	32	97.0%
32	Derby	1,460	1,413	47	96.8%
33	Doncaster	1,637	1,583	54	96.7%
34	Gateshead	1,377	1,332	45	96.7%
35	Adur & Worthing	2,856	2,758	98	96.6%
36	Wakefield	1,770	1,707	63	96.4%
37	Aberdeen	701	675	26	96.3%
38	North East Derbyshire	1,103	1,062	41	96.3%
39	Basingstoke & Deane	1,799	1,730	69	96.2%
40	Canterbury	1,936	1,863	73	96.2%
41	North Tyneside	1,244	1,195	49	96.1%
42	Lewes & Eastbourne	293	281	12	95.9%
43	Mid Sussex	1,182	1,134	48	95.9%
44	Forest of Dean	544	521	23	95.8%
45	Norwich	1,397	1,339	58	95.8%
46	City of Edinburgh	1,630	1,558	72	95.6%
47	Cotswold	2,282	2,181	101	95.6%
48	Sunderland	1,019	974	45	95.6%
49	West Oxfordshire	914	874	40	95.6%
50	Gedling	992	947	45	95.5%
51	Barnsley	3,843	3,666	177	95.4%
52	North Northamptonshire	542	517	25	95.4%
53	Darlington	443	422	21	95.3%
54	Horsham	2,125	2,025	100	95.3%
55	Tewkesbury	1,256	1,197	59	95.3%
56	Broxtowe	1,363	1,297	66	95.2%
57	Cannock Chase	483	460	23	95.2%
58	Telford & Wrekin	2,582	2,457	125	95.2%
59	Torfaen	538	512	26	95.2%
60	Bath & NE Somerset	5,021	4,777	244	95.1%
61	Chichester	400	380	20	95.0%
62	North Somerset	3,146	2,981	165	94.8%
63	Flintshire	575	544	31	94.6%
64	Babergh Mid Suffolk	509	480	29	94.3%
65	Dudley	4,051	3,822	229	94.3%
66	East Cambridgeshire	1,288	1,213	75	94.2%
67	Nottingham	977	920	57	94.2%
68	Test Valley	703	662	41	94.2%
69	Dorset	708	666	42	94.1%
70	York	2,435	2,292	143	94.1%
71	Lancaster	354	332	22	93.8%
72	Brighton & Hove	506	474	32	93.7%
73	Stevenage	1,128	1,057	71	93.7%
74	Warwick	3,625	3,396	229	93.7%
75	Great Yarmouth	378	353	25	93.4%
76	South Downs	939	876	63	93.3%
77	Camden	3,282	3,059	223	93.2%
78	Solihull	1,279	1,192	87	93.2%
79	Cambridge	1,044	972	72	93.1%
80	Cheshire East	2,071	1,928	143	93.1%
81	Rutland	983	914	69	93.0%
82	Sandwell	2,809	2,613	196	93.0%
83	Swindon	1,075	1,000	75	93.0%
84	Wandsworth	5,992	5,572	420	93.0%
85	Ceredigion	337	313	24	92.9%
86	Tonbridge & Malling	1,502	1,395	107	92.9%
87	Dover	890	826	64	92.8%
88	Rotherham	778	721	57	92.7%
89	Chorley	856	793	63	92.6%
90	Hammersmith & Fulham	5,296	4,902	394	92.6%
91	Three Rivers	440	407	33	92.5%
92	New Forest	2,406	2,222	184	92.4%
93	Sheffield	1,561	1,440	121	92.2%
94	Southwark	3,757	3,462	295	92.1%
95	Isle of Wight	1,381	1,271	110	92.0%
96	Luton	1,839	1,691	148	92.0%
97	Thanet	5,791	5,315	476	91.8%
98	Manchester	2,381	2,181	200	91.6%
99	Exeter	1,020	933	87	91.5%
100	Wigan	590	540	50	91.5%
101	Rushcliffe	2,268	2,073	195	91.4%
102	Selby	789	721	68	91.4%
103	Bassetlaw	715	652	63	91.2%
104	Lichfield	585	533	52	91.1%
105	Bristol	5,501	5,000	501	90.9%
106	Oldham	2,361	2,143	218	90.8%
107	South Gloucestershire	3,783	3,434	349	90.8%
108	Bury	1,150	1,042	108	90.6%
109	Trafford	5,917	5,352	565	90.5%
110	Kingston upon Hull	1,091	986	105	90.4%
111	Hastings	681	614	67	90.2%
112	Newport	643	579	64	90.0%
113	Reigate & Banstead	2,551	2,297	254	90.0%
114	Kensington & Chelsea	3,192	2,864	328	89.7%
115	Surrey Heath	1,177	1,055	122	89.6%
116	Calderdale	1,303	1,162	141	89.2%
117	Kirklees	5,890	5,256	634	89.2%
118	Oxford	1,277	1,139	138	89.2%
119	Portsmouth	2,254	2,010	244	89.2%
120	Dartford	1,944	1,733	211	89.1%
121	Leeds	10,080	8,973	1,107	89.0%
122	Liverpool	987	877	110	88.9%
123	Sefton	426	378	48	88.7%
124	Spelthorne	296	261	35	88.2%
125	Haringey	4,275	3,760	515	88.0%
126	Bradford	5,925	5,202	723	87.8%
127	Sevenoaks	1,735	1,522	213	87.7%
128	Westminster	3,068	2,691	377	87.7%
129	Glasgow	1,282	1,123	159	87.6%
130	Runnymede	3,487	3,055	432	87.6%
131	Epsom & Ewell	2,239	1,960	279	87.5%
132	Birmingham	13,248	11,547	1,701	87.2%
133	Gloucester	949	827	122	87.1%
134	Pendle	520	453	67	87.1%
135	Hart	2,121	1,836	285	86.6%
136	Newark & Sherwood	1,039	899	140	86.5%
137	Oadby & Wigston	727	623	104	85.7%
138	Caerphilly	439	376	63	85.6%
139	Windsor & Maidenhead	1,934	1,652	282	85.4%
140	Hackney	3,697	3,142	555	85.0%
141	Castle Point	954	810	144	84.9%
142	Hounslow	26,504	22,511	3,993	84.9%
143	Tameside	958	813	145	84.9%
144	Slough	2,671	2,251	420	84.3%
145	Coventry	475	400	75	84.2%
146	Brentwood	3,747	3,150	597	84.1%
147	Ealing	22,565	18,748	3,817	83.1%
148	Hertsmere	924	767	157	83.0%
149	Swansea	604	500	104	82.8%
150	Bexley	7,902	6,527	1,375	82.6%
151	Richmond	6,906	5,682	1,224	82.3%
152	Bromley	10,946	9,001	1,945	82.2%
153	Lambeth	5,992	4,925	1,067	82.2%
154	Havering	8,298	6,773	1,525	81.6%
155	Guildford	3,726	3,035	691	81.5%
156	Merton	5,617	4,576	1,041	81.5%
157	Croydon	10,142	8,224	1,918	81.1%
158	Maldon	660	534	126	80.9%
159	Islington	11,660	9,405	2,255	80.7%
160	Tower Hamlets	1,827	1,470	357	80.5%
161	Sutton	6,821	5,419	1,402	79.4%
162	Enfield	9,329	7,347	1,982	78.8%
163	Newham	4,353	3,420	933	78.6%
164	East Hertfordshire	5,178	4,063	1,115	78.5%
165	Harrow	4,812	3,762	1,050	78.2%
166	Redbridge	12,628	9,847	2,781	78.0%
167	Thurrock	3,518	2,742	776	77.9%
168	Hillingdon	9,930	7,701	2,229	77.6%
169	Barnet	17,196	13,051	4,145	75.9%
170	Lewisham	4,494	3,390	1,104	75.4%
171	Waltham Forest	7,930	5,971	1,959	75.3%
172	Kingston	7,226	5,419	1,807	75.0%
173	Barking & Dagenham	2,715	1,970	745	72.6%
174	Brent	12,106	8,792	3,314	72.6%
175	Greenwich	5,373	3,561	1,812	66.3%
176	Cardiff	265	167	98	63.0%

Found your council? See what's happening at street level →

What the data tells us

1

Where you live changes everything. The gap between the best council (Mid Devon, 100.0%) and the worst (Cardiff, 63.0%) is 37.0%. Same project, completely different odds.

2

69,267 rear extension applications have been refused since 2020. Each one cost the homeowner time and money. Most of those refusals were predictable from the local data.

3

National averages hide local variation. Your council rate is useful context. Your ward rate is better. But the comparable decisions near your specific property are the only real predictor of your outcome.

Rear Extension Approval Rates Across the UK

Check Your Postcode for Approval Chances

10 Best Councils for Rear Extensions

10 Hardest Councils for Rear Extensions

Your council's approval rate is just the starting point

All 176 Councils Ranked for Rear Extensions

What the data tells us

The UK average is meaningless. Your street isn't average.

More national planning data