We’ll send you a bill every six months. Your bill will show charges for every cubic metre (m3) of water used.
One cubic metre equals 1,000 litres which is an estimated 25 quick showers. It costs £2.7346 per m3 for clean water and £1.4721 per m3 for wastewater as of 1 April 2026.
Fixed charges for 2026-27
Once we’ve calculated your clean water and wastewater charges, we’ll add fixed charges. These cover our essential costs, such as pipe maintenance and bill and payment processing.
Type
Fixed charge
Fixed charge with surface water drainage rebate
Water
£66.87
Not applicable
Wastewater
£128.13
£80.43
San Diego, California: a city located in a semi-arid region which depends partly on desalinated water.
The monthly charges for a typical single-family domestic customer are:
Base fee: $35.53
0 - 10 HCF used are billed at $8.51 per HCF.
11 - 22 HCF used are billed at $9.50 per HCF.
Each HCF used after the initial 22 HCF is billed at $11.89 per HCF.
These guys charge a fixed fee based on the size of the meter. It looks like residential meters normally are either 5/8 inch, 3/4 inch, or 1 inch.
Water monthly fixed fee:
Meter Size
Rate ($)
5/8
8.69
3/4
10.64
1
13.50
Water usage fee:
Usage level
Rate per 1,000 gallons ($)
First 3,000 gallons
5.80
Next 17,000 gallons
9.87
Next 980,000 gallons
7.76
Over 1,000,000 gallons
6.50
Sewage monthly fixed fee:
Meter Size
Rate ($)
5/8
24.87
3/4
35.40
1
50.38
Sewage usage fee:
Per 1,000 Gallons: 8.66
At a current currency conversion rate of $1.3565 for £1, and with a cubic meter being 0.35314667 HCF and 0.26417205 thousand-gallons:
Six month residential water cost:
Source
Fixed Six-month Water Fee (£)
Per cubic meter (£)
Thames Water
66.87
2.73
City of San Diego (starting rate)
78.58
2.22
City of San Diego (maximum rate)
78.58
3.10
City of New Orleans (lowest rate)
38.43
1.23
City of New Orleans (maximum rate)
59.71
1.27
Six month residential wastewater cost
(for Thames Water, taking into account the rebate, and for San Diego, disregarding the limit that may be charged a customer):
Source
Fixed Six-month Wastewater Fee (£)
Per cubic meter(£)
Thames Water
80.43
1.47
City of San Diego
49.89
1.54
City of New Orleans (minimum rate)
110.00
1.69
City of New Orleans (maximum rate)
222.83
1.69
So, looking at that, a few things stand out. First, London is an old city, and I’d vaguely imagine has a lot of elderly sewers and such that might cost a lot to maintain. Going into this, I had guessed that infrastructure was maybe where any major Thames Water cost was coming from. But actually, the fixed sewage costs aren’t that much higher than San Diego (a relatively-young city), and are considerably lower than New Orleans’ fixed sewage costs. So unless, for some reason, the customer fee structure doesn’t reflect the cost structure for one or more of the organizations, that kills that theory.
And the Thames Water per-usage sewer rates are lower than the rates in both American cities.
Fixed water rates are in-between New Orleans and San Diego. I’d expect that some of San Diego’s fixed costs need to go to things like the San Diego Aqueduct system, to bring water from the closest sources of surface water, which isn’t something that’d be needed in London. But I’d also imagine that London has its own complexities, like older infrastructure.
The per-unit water usage rates for Thames Water, on the other hand, are relatively high — towards the upper end of San Diego’s per-unit usage rates, and as I said, San Diego relies in part on desalinated water, which should be more-expensive as a source than surface water (and which London could certainly hypothetically avail itself of). Thames Water per-unit water rates are also much higher than those in New Orleans. It does seem to me that there’s plausibly a way to get per-usage water rates down for Thames Water.
I’m kind of curious how it compares to some of the cities here in the US.
Thames Water, London, UK
https://www.thameswater.co.uk/help/account-and-billing/understand-your-bill/metered-customers
San Diego, California: a city located in a semi-arid region which depends partly on desalinated water.
https://www.sandiego.gov/public-utilities/customer-support/water-billing-rates
https://www.sandiego.gov/public-utilities/customer-support/sewer-billing-rates
New Orleans, Lousiana: a city located at the mouth of the Mississippi, as London is located at the mouth of the Thames:
https://www.swbno.org/CustomerService/RatesFeesAndCharges
These guys charge a fixed fee based on the size of the meter. It looks like residential meters normally are either 5/8 inch, 3/4 inch, or 1 inch.
Water monthly fixed fee:
Water usage fee:
Sewage monthly fixed fee:
Sewage usage fee:
At a current currency conversion rate of $1.3565 for £1, and with a cubic meter being 0.35314667 HCF and 0.26417205 thousand-gallons:
Six month residential water cost:
Six month residential wastewater cost
(for Thames Water, taking into account the rebate, and for San Diego, disregarding the limit that may be charged a customer):
So, looking at that, a few things stand out. First, London is an old city, and I’d vaguely imagine has a lot of elderly sewers and such that might cost a lot to maintain. Going into this, I had guessed that infrastructure was maybe where any major Thames Water cost was coming from. But actually, the fixed sewage costs aren’t that much higher than San Diego (a relatively-young city), and are considerably lower than New Orleans’ fixed sewage costs. So unless, for some reason, the customer fee structure doesn’t reflect the cost structure for one or more of the organizations, that kills that theory.
And the Thames Water per-usage sewer rates are lower than the rates in both American cities.
Fixed water rates are in-between New Orleans and San Diego. I’d expect that some of San Diego’s fixed costs need to go to things like the San Diego Aqueduct system, to bring water from the closest sources of surface water, which isn’t something that’d be needed in London. But I’d also imagine that London has its own complexities, like older infrastructure.
The per-unit water usage rates for Thames Water, on the other hand, are relatively high — towards the upper end of San Diego’s per-unit usage rates, and as I said, San Diego relies in part on desalinated water, which should be more-expensive as a source than surface water (and which London could certainly hypothetically avail itself of). Thames Water per-unit water rates are also much higher than those in New Orleans. It does seem to me that there’s plausibly a way to get per-usage water rates down for Thames Water.