Hamas is expected to release all hostages still in captivity as part of a ceasefire deal.
The 20 living captives, who are all men, have been held for more than two years after they were among 251 people kidnapped when Hamas-led militants launched a surprise attack on Israel on 7 October 2023.
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The bodies of another 28 hostages who were killed in captivity are also expected to be returned to Israel.
Exact details of the handover are still unclear but this is what we know.
When is the deadline?
Hamas have until 10am UK time to release the hostages as part of Donald Trump's 20-point peace plan.
What time will they actually be freed?
There have been mixed messages about the exact timings and Israel's prime minister Benjamin Netanyahu said Israel was ready to "immediately" receive the captives.
US vice-president JD Vance said earlier on Sunday the hostages would be released "any moment now".
But the most concrete statement we've heard comes from Israeli government spokeswoman Shosh Bedrosian, who said they will be released "early Monday morning".
The Times of Israel has reported that could be as early as 2am UK time.
Hamas has previously indicated it would take more time to hand over the bodies of the hostages who have died to Israel.
How will the handover work?
Israeli government spokeswoman Shosh Bedrosian said the 20 hostages are expected to be released together at one time to the Red Cross.
She said they will be taken in "six to eight" vehicles without "any sick displays by Hamas", referring to the previous release ceremonies staged by the militant group.
The hostages will then be driven to forces inside Israel-controlled parts of Gaza before they are transferred to southern Israel, where they will reunite with their families.
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"Israel is ready if a living hostage requires any urgent medical attention, they will be brought to a medical facility immediately," she said.
She said the "entire nation of Israel" will embrace those killed in captivity and "ensure proper Jewish burials".
The US president is expected to arrive in Israel on Monday morning and will meet with families of the hostages, according to a schedule released by the White House.
Where will they spend their first nights of freedom?
Pictures released by the Israeli government show the light airy rooms where the hostages will be welcomed.
The comfortable chairs, big television, and bedrooms with clean sheets and baskets full of toiletries will be a world away from the dark Hamas tunnels where they have been kept in Gaza for the past 734 days.
Sky News was given special access to one of the teams in the Rabin Medical Centre in Petah Tikva, a city northeast of Tel Aviv, which is preparing to receive them.
Director of Nursing Dr Michal Steinman said the hostages will be given their own private room, where a gift basket filled with thoughtful items such as a teddy, a blanket, slippers and a phone charger awaits them.
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