Water companies have said most customers have had their supplies restored after burst pipes caused shortages, however some lingering issues remain five days after problems first emerged.
Ministers have announced a review into how water firms handled last week's bad weather after thousands of homes were left without their supply.
Industry regulator Ofwat has criticised companies for their lack of preparation, support and communication with customers, saying a number of firms "appeared to have fallen well short" on forward planning "leaving some customers high and dry".
On Wednesday Severn Trent said all of its customers in south Birmingham should have seen their supplies restored back to normal and the company was closing two stations distributing bottled water.
In London, Thames Water said a large number of customers in the SW and SE postcodes had their supply back, although localised airlocks continued to affect some properties.
As the company worked to iron out the issues an important route into south London was closed after a water pipe burst, although it is not known if it was directly linked to the wider problems.
Welsh Water warned of a risk of leaks and bursts as supplies were reconnected.
On Tuesday night the firm said the "vast majority" of customers whose supplies had been interrupted had been restored, although 1,000 properties in rural areas in parts of east Anglesey, mid-Ceredigion and rural Pembrokeshire were still "off-supply".
South East Water also said some people in Sussex remained without water, although teams had reconnected restored supplies to 15,000 customers in 24 hours.
Ofwat chief executive Rachel Fletcher criticised some water companies, saying they lacked readiness and support for customers.
She said: "When the taps are back on, we will take a long, hard look at what has happened here and we won't hesitate to intervene if we find that companies have not had the right structures and mechanisms in place to be resilient enough."
Environment Minister Therese Coffey said regulator Ofwat would be encouraged to take action "to ensure water companies up their game".
The environment minister said a review would consider whether statutory compensation should be paid, adding that it was for water companies to consider how they can compensate customers on a discretionary basis.