The company lifted its boil warning for all affected customers in Northamptonshire early this afternoon.
"This decision has been taken in conjunction with the Health Authority and local authorities," said a spokesman.
"The decision to lift the notice for all affected customers has been taken following an accelerated cleaning and flushing programme over the week.
For all the water crisis news - click here"Anglian Water would like to thank its employees and suppliers who have worked tirelessly to make this possible."
Green 'all clear' notices will be posted to Northampton customers tonight. The 'all clear' notices for customers in Daventry will be dispatched over the weekend.
"All customers are advised that they may start drinking their tap water immediately without needing to boil it first," added the spokesman.
Anglian Water said is to make a goodwill payment to customers in Northampton, Daventry and the surrounding areas for the inconvenience caused by the cryptosporidium in the water supply.
It is estimated that total goodwill payments will approach £3m and this cost will not be passed on to customers in any form.
The payment will be made in the form of a credit equivalent to six weeks' free water supply, based on customers' past annual water bills.
This will be up to a maximum of £30 per household and full details will follow in a letter to customers.
"We believe that this is the fairest approach as it is proportional to customers' water usage and therefore benefits those that have been most inconvenienced," added the spokesman.
Anglian Water chief executive Jonson Cox, said: "Our customers have been understanding, patient and helpful throughout this incident.
"I am delighted that today we are able to lift this notice for all of those affected.
"I am particularly pleased that we have been able to remove the restrictions for customers in the Daventry area up to a fortnight earlier than originally anticipated.
"We apologise unreservedly to our customers for the inconvenience caused by asking them to boil their drinking water and thank them for their tolerance and patience while we put it right."
