CHICAGO — Hilton Hotels Corp. yesterday announced tentative agreement with UNITE HERE on a new contract covering 2,300 employees at four Chicago hotels.

The three-year accord is subject to ratification by union members and covers the Hilton Chicago, Hilton O'Hare Airport, The Drake and the Palmer House Hilton. It features improved pay, pension and healthcare.

Hilton Hotels said details will be released after the ratification vote on Wednesday.

The agreement is the second negotiated by Hilton and the union in the past five weeks. The sides reached agreement July 29 on a contract for New York City.

In Hawai'i, Hilton has not yet reached agreement on a new contract with the union.

UNITE HERE was created by the merger of the Union of Needletrades, Industrial and Textile Employees and the Hotel Employees and Restaurant Employees.