Devon & Cornwall · Water company

South West Water Hardness

Average 80 ppm across 129 postcodes served.

  • Range 27–138 ppm
  • Region Devon & Cornwall
  • Postcodes 129
Company average
80
ppm CaCO₃
Slightly Hard
Soft
Moderate
Hard
Very hard
0100200300400+
80
Avg ppm
27
Min ppm
138
Max ppm
129
Postcodes

Free Hard Water Action Plan

Enter your email and we will send the fixes that actually work for your hardness level, plus what to skip.

South West Water Water Hardness Summary

South West Water water is slightly hard, averaging 80 ppm as calcium carbonate, ranging from 27 to 138 ppm across 129 postcode districts in Devon & Cornwall.

Average hardness80 ppm (Slightly Hard)
Hardness range27 to 138 ppm
ClassificationSlightly Hard
Districts served129
RegionDevon & Cornwall

About South West Water

South West Water serves 1.8 million customers across Devon and Cornwall. The region's granite geology produces naturally soft water, among the softest in England.

At 80 ppm on average, South West Water ranks as slightly hard water. See how it compares across the UK in our 50 softest water areas ranking.

Worth reading: our water softener guide compares the options for South West Water customers, and our limescale removal guide has quick fixes for kettles, taps, and boilers.

Cross-check this against South West Water's own data: South West Water water hardness report. Most of the region is soft water, except East Devon; use the postcode lookup on this page to find your address's specific water quality.

Comparison

South West Water vs Other UK Water Companies

Average hardness across the 15 largest UK water suppliers, hardest first. Your supplier is highlighted.

RankWater companyAvg ppmClassificationDistricts
1 Anglian Water 321 ppm Very Hard 261
2 Thames Water 302 ppm Very Hard 412
3 South East Water 297 ppm Hard 17
4 Affinity Water 268 ppm Hard 32
5 Southern Water 263 ppm Hard 131
6 Portsmouth Water 261 ppm Hard 34
7 SES Water 239 ppm Hard 7
8 Wessex Water 231 ppm Hard 123
9 Severn Trent Water 222 ppm Hard 345
10 Yorkshire Water 215 ppm Hard 217
11 Northumbrian Water 101 ppm Slightly Hard 122
12 South West Water 80 ppm Slightly Hard 129
13 United Utilities 77 ppm Slightly Hard 242
14 Welsh Water (Dwr Cymru) 68 ppm Slightly Hard 214
15 Scottish Water 54 ppm Soft 3
Distribution

Hardness Breakdown

26
Soft
(20%)
85
Slightly Hard
(66%)
18
Moderate
(14%)
0
Hard
(0%)
0
Very Hard
(0%)
All areas

Areas Served by South West Water

Every postcode district, sorted by hardness.

Postcode Town Hardness PPM Level
EX39 Bideford
138
138 ppm Moderately Hard
PL9 Plymouth
138
138 ppm Moderately Hard
EX38 Torrington
137
137 ppm Moderately Hard
PL8 Plymouth
137
137 ppm Moderately Hard
EX37 Umberleigh
136
136 ppm Moderately Hard
PL7 Plymouth
136
136 ppm Moderately Hard
EX36 South Molton
135
135 ppm Moderately Hard
PL6 Plymouth
135
135 ppm Moderately Hard
EX35 Lynton
134
134 ppm Moderately Hard
PL5 Plymouth
134
134 ppm Moderately Hard
EX34 Ilfracombe
133
133 ppm Moderately Hard
PL4 Plymouth
133
133 ppm Moderately Hard
EX33 Braunton
132
132 ppm Moderately Hard
PL3 Plymouth
132
132 ppm Moderately Hard
EX32 Barnstaple
131
131 ppm Moderately Hard
PL2 Plymouth
131
131 ppm Moderately Hard
EX31 Barnstaple
130
130 ppm Moderately Hard
PL1 Plymouth
130
130 ppm Moderately Hard
PL35 Boscastle
115
115 ppm Slightly Hard
PL34 Tintagel
114
114 ppm Slightly Hard
PL33 Delabole
113
113 ppm Slightly Hard
PL32 Camelford
112
112 ppm Slightly Hard
PL31 Bodmin
111
111 ppm Slightly Hard
PL30 Bodmin
110
110 ppm Slightly Hard
TR27 Hayle
109
109 ppm Slightly Hard
TR26 St Ives
108
108 ppm Slightly Hard
TR9 St Columb
107
107 ppm Slightly Hard
TR8 Newquay
106
106 ppm Slightly Hard
TR7 Newquay
105
105 ppm Slightly Hard
TR6 Perranporth
104
104 ppm Slightly Hard
TR21 Isles Of Scilly
103
103 ppm Slightly Hard
TR5 St Agnes
103
103 ppm Slightly Hard
TR20 Penzance
102
102 ppm Slightly Hard
TR4 Truro
102
102 ppm Slightly Hard
TR3 Truro
101
101 ppm Slightly Hard
EX24 Colyton
100
100 ppm Slightly Hard
TR2 Truro
100
100 ppm Slightly Hard
EX23 Bude
99
99 ppm Slightly Hard
TR1 Truro
99
99 ppm Slightly Hard
EX22 Holsworthy
98
98 ppm Slightly Hard
EX21 Beaworthy
97
97 ppm Slightly Hard
EX20 Okehampton
96
96 ppm Slightly Hard
PL29 Port Isaac
86
86 ppm Slightly Hard
PL28 Padstow
85
85 ppm Slightly Hard
PL27 Wadebridge
84
84 ppm Slightly Hard
EX9 Budleigh Salterton
83
83 ppm Slightly Hard
PL26 St Austell
83
83 ppm Slightly Hard
EX8 Exmouth
82
82 ppm Slightly Hard
PL25 St Austell
82
82 ppm Slightly Hard
EX7 Dawlish
81
81 ppm Slightly Hard
PL24 Par
81
81 ppm Slightly Hard
EX6 Exeter
80
80 ppm Slightly Hard
PL23 Fowey
80
80 ppm Slightly Hard
EX5 Exeter
79
79 ppm Slightly Hard
PL22 Lostwithiel
79
79 ppm Slightly Hard
EX4 Exeter
78
78 ppm Slightly Hard
PL21 Ivybridge
78
78 ppm Slightly Hard
TR19 Penzance
78
78 ppm Slightly Hard
EX3 Exeter
77
77 ppm Slightly Hard
PL20 Yelverton
77
77 ppm Slightly Hard
TR18 Penzance
77
77 ppm Slightly Hard
EX2 Exeter
76
76 ppm Slightly Hard
TR17 Marazion
76
76 ppm Slightly Hard
EX1 Exeter
75
75 ppm Slightly Hard
TR16 Redruth
75
75 ppm Slightly Hard
TQ9 Totnes
74
74 ppm Slightly Hard
TR15 Redruth
74
74 ppm Slightly Hard
TQ8 Salcombe
73
73 ppm Slightly Hard
TR14 Camborne
73
73 ppm Slightly Hard
EX19 Winkleigh
72
72 ppm Slightly Hard
TQ7 Kingsbridge
72
72 ppm Slightly Hard
TR13 Helston
72
72 ppm Slightly Hard
EX18 Chulmleigh
71
71 ppm Slightly Hard
TQ6 Dartmouth
71
71 ppm Slightly Hard
TR12 Helston
71
71 ppm Slightly Hard
EX17 Crediton
70
70 ppm Slightly Hard
TA9 Highbridge
70
70 ppm Slightly Hard
TQ5 Brixham
70
70 ppm Slightly Hard
TR11 Falmouth
70
70 ppm Slightly Hard
EX16 Tiverton
69
69 ppm Slightly Hard
TA8 Burnham On Sea
69
69 ppm Slightly Hard
TQ4 Paignton
69
69 ppm Slightly Hard
TR10 Penryn
69
69 ppm Slightly Hard
EX15 Cullompton
68
68 ppm Slightly Hard
TA7 Bridgwater
68
68 ppm Slightly Hard
TQ3 Paignton
68
68 ppm Slightly Hard
EX14 Honiton
67
67 ppm Slightly Hard
TA6 Bridgwater
67
67 ppm Slightly Hard
TQ2 Torquay
67
67 ppm Slightly Hard
EX13 Axminster
66
66 ppm Slightly Hard
TA5 Bridgwater
66
66 ppm Slightly Hard
TQ1 Torquay
66
66 ppm Slightly Hard
EX12 Seaton
65
65 ppm Slightly Hard
TA4 Taunton
65
65 ppm Slightly Hard
EX11 Ottery St Mary
64
64 ppm Slightly Hard
TA24 Minehead
64
64 ppm Slightly Hard
TA3 Taunton
64
64 ppm Slightly Hard
EX10 Sidmouth
63
63 ppm Slightly Hard
TA2 Taunton
63
63 ppm Slightly Hard
TA23 Watchet
63
63 ppm Slightly Hard
TA1 Taunton
62
62 ppm Slightly Hard
TA22 Dulverton
62
62 ppm Slightly Hard
TA21 Wellington
61
61 ppm Slightly Hard
TA20 Chard
60
60 ppm Soft
PL19 Tavistock
53
53 ppm Soft
PL18 Gunnislake
52
52 ppm Soft
PL17 Callington
51
51 ppm Soft
PL16 Lifton
50
50 ppm Soft
PL15 Launceston
49
49 ppm Soft
PL14 Liskeard
48
48 ppm Soft
PL13 Looe
47
47 ppm Soft
PL12 Saltash
46
46 ppm Soft
PL11 Torpoint
45
45 ppm Soft
PL10 Torpoint
44
44 ppm Soft
TA19 Ilminster
36
36 ppm Soft
TA18 Crewkerne
35
35 ppm Soft
TA17 Hinton St George
34
34 ppm Soft
TA16 Merriott
33
33 ppm Soft
TA15 Montacute
32
32 ppm Soft
TQ14 Teignmouth
32
32 ppm Soft
TA14 Stoke Sub Hamdon
31
31 ppm Soft
TQ13 Newton Abbot
31
31 ppm Soft
TA13 South Petherton
30
30 ppm Soft
TQ12 Newton Abbot
30
30 ppm Soft
TA12 Martock
29
29 ppm Soft
TQ11 Buckfastleigh
29
29 ppm Soft
TA11 Somerton
28
28 ppm Soft
TQ10 South Brent
28
28 ppm Soft
TA10 Langport
27
27 ppm Soft

Test Your Water on South West Water

At 80 ppm on average, your water is slightly hard. A home testing kit lets you verify the exact hardness for your postcode and check for other contaminants.

TESPERT 16-in-1 Water Testing Kit

From ~£10

Home water test strips that check hardness, pH, chlorine, lead, and 12 other parameters. Results in around 60 seconds. 125 strips per pack.

View on Amazon
FAQ

Common questions about South West Water water hardness

How do I check South West Water hardness by postcode?
Enter your postcode in the checker on the WaterHard.uk homepage, or find your district in the table above. South West Water serves 129 postcode districts across Devon & Cornwall, ranging from 27 to 138 ppm.
Is there a South West Water hardness checker or map?
South West Water publishes water quality data by postcode, but it can be scattered across PDF reports. WaterHard.uk compiles it into the searchable table above so you can find your district's reading in one place.
How hard is South West Water water in my area?
It depends on your exact postcode. South West Water supplies range from 27 ppm to 138 ppm, averaging 80 ppm (slightly hard) across 129 postcode districts in Devon & Cornwall. Use the table above to find your specific district.
Is South West Water water hard or soft?
South West Water averages 80 ppm, classified as slightly hard. Most households on South West Water see little to no limescale build-up, though individual postcodes can vary, so check the table above for your district.
Get a free quote