The final phase of the roadmap out of lockdown will see an end to restrictions on the size of weddings and other gatherings, the reopening of nightclubs and the return of large crowds for events.
But the final unlocking, dubbed Freedom Day, will depend on whether England has met the criteria on four tests.
Here is a detailed look at the data that could decide if England’s lockdown ends on June 21:
1. Have enough people been vaccinated?
Around 78.5% of adults in England have received their first Covid-19 vaccine and more than half, 57%, are fully vaccinated.
By now, most people in the older age groups have had their jabs, with many of the unvaccinated being people in their 20s and 30s.
The latest data from NHS England shows vaccinations up to June 12. It suggests more than 90% of people aged 70 and over have received two jabs.
The government has said it is on target to offer all people aged 50 and over both doses of vaccine by June 21, and for all adults to be offered a first jab by the end of July.
The vaccine rollout appears to be successful so far, and even one dose will protect people against severe illness from coronavirus. But vaccines are not 100% effective and not everyone has been vaccinated. And there are questions about whether existing vaccines can hold out against the new Delta variant.
ITV News Science Editor Tom Clarke said: "We have to remember the vaccine, although they're really effective, even if they're 95% effective, that still leaves hundreds of thousands of people vulnerable to serious Covid.
"If the numbers get high enough, theoretically, and the mathematical modelling blows this out we could still see a third wave as large as the one we just come through."
2. Are vaccines reducing hospitalisations and deaths?
Although cases are rising, hospitalisations and deaths remain low. This is evidence that vaccines are protecting the vulnerable.
Tom Clarke told ITV News' Coronavirus: What You Need To Know podcast that when the Alpha (Kent) variant was in circulation, 8% to 9% of people who got infected with it would end up in hospital.
The evidence from Bolton, where the Delta variant was first detected, shows that around 1% of people with the variant are hospitalised.
This may be because it is younger people who are being hospitalised - possibly because a large percentage of the older population have been fully vaccinated - but Tom Clarke said it would be a few more weeks before the data showed the full impact of the rising infection rates.
Coronavirus: What you need to know - How long could the Delta variant delay Freedom Day?
Vaccines have averted around 42,000 hospital admissions and more than 14,000 deaths in older adults in England up to May 30, according to estimates from Public Health England.
However, hospital cases are rising again.
A total of 158 hospital admissions of Covid-19 patients England were reported for June 9, according to NHS England. This is up from 101 a week earlier and is the highest number since April 12.
The total number of Covid-19 patients in hospital in England was 884, as of 8am on June 11. This is up from 805 a week earlier.
The north west of England and London is seeing a rise in Covid patients in hospital - although other regions have not yet seen a similar trend. In all areas in England, the level of coronavirus patients in hospital is still below that of the peak of the second wave.
3. How high are infection levels and case rates?
Infection levels and cases are rising as the country unlocks.
The rate of new confirmed cases of Covid-19 in England is at its highest level for three months - 64.7 cases per 100,000 people were recorded in the seven days to June 8.
But this still pales in comparison the rate at the peak of the second wave in early January, which was 680.6 per 100,000 people.
Around nine in 10 local authority areas in England (89%) are recording a rise in rates.
The biggest increases are in Lancashire, South Ribble and Blackburn with Darwen.
But the rise in cases may not be a problem in itself, if these infections are not leading to hospitalisations and deaths.
Tom Clarke explains: "There is the chance that spread causes a huge number of cases in unvaccinated people, so that's children, teenagers, young adults who haven't been vaccinated, and they're not going to be a huge problem because they don't get serious illness or die.
"But if the numbers get large enough, the virus could spread into the parts of the population, which is, is vulnerable but not vaccinated, and there are hundreds of thousands of people over 50 who have still not had both doses of the vaccine or who haven't been able to be vaccinated one reason or another."
4. Could new variants pose a danger to public health?
The Delta variant of coronavirus, first identified in India, is driving the rise in infections and case rates, and is now responsible for up to 96% of new Covid-19 cases, Public Health England said on Friday.
It is also believed to have a 60% increased risk of household transmission compared to the Alpha variant, which originated in Kent at the end of last year.
ITV News Science Editor Tom Clarke says the advisors he has spoken to say that, looking at the numbers, "it really all comes down to the Delta variant".
Speaking on the ITV News Coronavirus: What You Need To Know podcast, Tom Clarke said it was "possibly the fastest growth rate we've seen in in England in terms of the variant, that is a concerning amount of spread".
"You don't want to be making any major changes to your public health measures when you're dealing with something that's spreading as alarmingly as that."
However, Public Health England said it was “encouraging” that the increase is “not yet accompanied by a similarly large increase in hospitalisations”.
It added that the vaccination programme is continuing to reduce the impact of the variant.
Out of 383 cases of the Delta variant in England up to June 7 that required an overnight stay in A&E, 251 (66%) were unvaccinated, 66 (17%) were more than 21 days after their first dose of vaccine and 42 (11%) were more than 14 days after their second.
And of the 42 deaths in England to June 7 of people who had the Delta variant and died within 28 days of a positive test, 23 were unvaccinated, seven were more than 21 days after their first dose of vaccine and 12 were more than 14 days after their second dose.