Worcester is prepared to give Amazon a $500 million property tax break if the Seattle e-commerce leader agrees to locate its future second headquarters in New England’s second-largest city.

City and regional economic development officials are pitching a 98-acre site containing 16 parcels along Route 20. Along with $500 million in tax increment financing, the incentive package calls for a 100 percent personal property tax exemption, state investment tax credits, $1 million in job creation grants, district improvement financing and MassWorks infrastructure grants.

The Worcester proposal cites the city’s affordability, higher education institutions, biotech cluster and downtown redevelopment projects.

Thursday is the deadline for communities to submit proposals to Amazon, which is seeking up to 8 million square feet of office space including 500,000 square feet available in 2019. Amazon’s request for proposals mentions its interest in a minimum 100-acre parcel as well as space within existing buildings.

Boston Mayor Marty Walsh is expected to present the 161-acre Suffolk Downs racetrack property on the East Boston-Revere border as the city’s top choice.

Somerville Mayor Joseph Curtatone proposes “Amazon On The Orange Line” with a mix of sites including Assembly Row in Somerville, The Hub On Causeway at Boston’s North Station and Cambridge’s NorthPoint.

Union Point, a 1,400-acre former naval air station site in Abington, Rockland and Weymouth controlled by developer LStar Ventures, has the support of local officials in the three communities. And a regional proposal by Merrimack Valley towns offers the 168-acre Osgood Landing property, a former Lucent Technologies facility in North Andover.