It means almost all legal restrictions on social contact will be removed.
But the prime minister said it was vital to proceed with "caution", warning "this pandemic is not over" .
The peak of the current wave is not expected before mid-August and could lead to between 1,000 and 2,000 hospital admissions per day, according to government scientists.
Central estimates from modellers advising the government also show that Covid deaths are expected to be between 100 and 200 per day at the peak, although there is a large amount of uncertainty.
Earlier, the health secretary told the House of Commons cases could reach 100,000 a day later in the summer but he did not believe this would put "unsustainable pressure on the NHS".
Vaccinations had created a "protective wall", which would mean we could "withstand a summer wave", Sajid Javid added.
Boris Johnson later told a Downing Street press conference that coronavirus "continues to carry risks for you and your family".
"We cannot simply revert instantly from Monday July 19 to life as it was before Covid," he said.
The prime minister added that he hoped the roadmap would be "irreversible" but "in order to have that, it has also got to be a cautious approach".
While virtually all legal restrictions will be lifted, some guidance will remain.
For example, the legal requirement to wear face coverings in some enclosed public places will be removed but Mr Javid said they were still "expected and recommended" in crowded indoor areas.
Nightclubs will also be allowed to reopen for the first time since March 2020 and capacity limits will be removed for all venues and events.
There will no longer be any limits on how many people can meet and the 1m-plus distancing rule will be removed.
But nightclubs and other venues with large crowds will be encouraged to use Covid status certification - so-called domestic vaccine passports - "as a matter of social responsibility", the prime minister said.
These would allow people to show they are double-jabbed, have had a negative test result or have natural immunity after recovering from Covid-19, using the NHS app.
In guidance published after the press conference, the government said it "reserves the right" to make certification mandatory in certain venues if necessary in the future.
Government guidance to work from home where possible will be lifted, but ministers are encouraging a gradual return to the workplace.
Mr Javid also said people should act with "personal responsibility" and "try to meet people outside where possible".
The requirement to self-isolate if you are contacted by NHS Test and Trace will remain in place until 16 August, when it will be relaxed for people who are fully vaccinated and for the under-18s. If someone tests positive for the virus they will still be legally required to self-isolate.
Wales is due to review its restrictions on 15 July, while Scotland is expected to move to level 0 - the lowest level of restrictions in its roadmap - on 19 July and lift most legal restrictions on 9 August. Northern Ireland is due to ease some Covid measures on 26 July.
Freedom Day, as it has been dubbed, is on.
But make no mistake this is not where England - and the rest of the UK for that matter - hoped it would be.
Hospital admissions will almost certainly rise above 1,000 a day in the coming weeks - similar to what the NHS would see in the depths of winter for all types of respiratory infection.
It's not enough to overwhelm the NHS, but it does mean less non-Covid care.
However, infection rates were always going to rise at this point of the unlocking and so the big question is when and at what point this wave will peak.
There's huge uncertainty about this. Small things can make a big difference, including how people behave.
That's why government scientists have pushed behind the scenes for ministers to change tone on mask-wearing in crowded indoor places - if nothing else it reinforces the message that infection rates still do matter.
But those same scientists are also in broad agreement that now is the best time, rather than wait until the autumn when other viruses like flu begin to circulate.
The decision is a gamble, but it's a calculated one, they say.
England's chief medical officer Prof Chris Whitty said the "overwhelming view" of the scientific community was that moving "slowly" through the next step of easing restrictions was "essential".
"The slower we take it, the fewer people will have Covid, the smaller the peak will be, and the smaller the number of people who go into hospital and die," he said.
By moving slowly, he said modelling suggested the pressure on the NHS would not be "unsustainable".
Prof Whitty said there was less agreement on the "ideal date" to lift restrictions as there is "no such thing as an ideal date" .
However, he said a further delay would mean opening up when schools return in autumn, or in winter, when the virus has an advantage and hospitals are under more pressure.
He added that while the numbers of people being admitted to hospital with Covid were "not trivial", they were rising at a much lower rate than previous waves.
Labour criticised the government's approach to unlocking on 19 July as "high risk" and "fatalistic".
Shadow health secretary Jonathan Ashworth told MPs in the Commons: "Instead of caution [the health secretary] is putting his foot down the on the accelerator while throwing the seat belt off."
"That means potentially thousands [of people] suffering debilitating Long Covid. It means, as more cases arise, potentially more escape and the threat of new more transmissible variants emerging," he added.
The British Chambers of Commerce said many businesses would be "sighing with relief" to get the green light to reopen but they "still don't have the full picture they desperately need to properly plan for unlocking".
Claire Walker, co-executive director, said: "Business leaders aren't public health experts and cannot be expected to know how best to operate when confusing and sometimes contradictory advice is coming from official sources."
On Monday, the UK recorded 34,471 new cases, as well as six deaths within 28 days of a positive test.
It is the sixth consecutive day cases have been above 30,000.
The number of deaths recorded on Mondays are often lower due to reporting lags over the weekend.
More than 45.9 million people - or 87% of adults in the UK - have now had at least one dose of a Covid-19 vaccine. And more than 34.8 million - around two-thirds of adults - have had both doses.
The final stage of England's roadmap out of lockdown, which was originally scheduled for 21 June, was delayed to allow more people to be vaccinated.
Mr Javid said the government was "on track" to beat its target to offer every adult a first dose by 19 July.
Boris Johnson set out England's reopening on 19 July: "The pandemic is not over"