Tokyo
Grade B — one disclosed assumption, under 1% of the bill — comparable, with the assumption printed. How the grade is set →
Two prices, and both are the tariff
The standing tariff charges 2.56 times what the household is billed while the relief runs, from 2026-05-01 to 2026-09-30. Nothing was repealed to produce the lower figure: basic charge waived in full for 13, 20 and 25 mm connections. It is funded by a transfer from the metropolitan general account. No application is required, so it is a feature of the charge rather than a discount somebody claims.
Four months, billed as the 5–6 and 7–8 months for a property read in an odd month and the 6–7 and 8–9 months for one read in an even month, with the first waived reading taken on 1 June. Modelled as a single month. The payable price is period-dependent in a way one monthly figure cannot express.
The issuer calls it a temporary special measure limited to this summer. The same measure ran in the summer of 2025. A measure the issuer calls limited to this summer has now happened two years running. Recorded as the issuer states it, with the repetition noted.
Out of the index basket. Temporary policy relief is live; the comparable figure is the structural one. A frozen base must not embed a policy that will expire while the base does not.
How much of the bill is wastewater
How much of the bill sits outside the volumetric rate
Both comparisons are proportions, so they hold across currencies. The bills themselves do not, and are not compared.
Cost by volume
A household on 5,000 litres a month pays about 73% more per litre than one on 25,000, because the fixed charges spread over less water.
Where the water comes from
Tokyo draws principally on the Tone and Ara river systems through the Bureau's treatment plants. No annual production figure with a year attached has been captured.