The reduction will come into effect from 11 June, and last until four weeks after sites are able to legally reopen.
From there the concession will be reduced from 90% to 50% for a further four weeks.
Once they reopen, tenants will also receive eight weeks of trade support when buying barrels of beer or cider from Greene King.
Greene King says that around £4m of rent concessions have been made in the Pub Partners business through its support fund to tied tenants, with all rents deferred for tenants since 17 March.
“By deferring rents before pubs were ordered to close we removed any immediate cashflow concerns for our partners and since then have reassured them that we would support them in every way possible when it came to rent and I’m very pleased to announce these latest measures today," says Wayne Shurvinton, managing director of Greene King Pub Partners.
“None of us are immune to the financial implications of pubs closing and we all have to work together to survive this existential threat to our industry. I’m grateful to every single one of our tenants who has worked with us and trusted that we were doing all we could to look after them.
“We feel we’ve played our part and it is critical the government continues to play its part in supporting our sector. The support so far is extremely welcome but as a tenant ourselves with over 500 landlords, we have not received rent concessions in the way we are offering them to our tenants and further support on rent payments is needed to support the recovery of the pubs sector.”
Earlier this month Greene King also set up an employee support fund, to help workers affected by the Coronavirus crisis.