Shops, hairdressers, gyms and outdoor hospitality will reopen on 12 April in England if strict conditions are met, under plans being set out by the PM.
Up to six people from separate households could be able to meet in beer gardens from that date.
The new four-step plan to ease lockdown could see all legal limits on social contact lifted by 21 June.
It requires four tests on vaccines, infection rates and new coronavirus variants to be met at each stage.
Prime Minister Boris Johnson told MPs the plan aimed to be "cautious but irreversible" and at every stage decisions would be led by "data not dates".
But he warned there was "no credible route to a zero-Covid Britain nor indeed a zero-Covid world".
It comes as the first data on the UK's coronavirus vaccine rollout suggests it is having a "spectacular" impact on stopping serious illness.
As part of the first step of the plan for easing lockdown in England:
Secondary school pupils will be required to wear face coverings in classrooms and shared spaces like corridors.
The second step from 12 April would see major parts of the economy permitted to reopen:
But wider social contact rules will continue to apply in all settings - meaning no indoor mixing between different households will be allowed.
Mr Johnson confirmed the end of hospitality curfews - and requirements to eat a substantial meal alongside alcohol.
Funerals continue with up to 30 people, and weddings with up to 15 guests.
The third step will come from 17 May - if the data allows - and will see the "rule of six" abolished for outdoor gatherings, replaced with a limit of 30 people:
Up to 30 people will be able to attend weddings, receptions, funerals and wakes.
The fourth step from 21 June will potentially see all legal limits on social contact removed, with the final closed sectors of the economy reopened - such as nightclubs.
The government hopes that - from this date - restrictions on weddings and funerals will also be abolished.
Must pass tests
The four conditions that must be met at each phase of lockdown easing are:
I'm a Accountant that has dealt with many SME's ( Small and Medium sized Enterprises) over the years, in all aspects of Accounting, Business advice etc.