Birchwood Park in Warrington has secured a 32,000 sq ft pre-let at the final phase of its 250,000 sq ft Bridgewater Place office scheme.
Landlord MEPC said it is an existing tenant but would not disclose the name. It is understood to be Serco Assurance.
The new letting is for 305 Bridgewater Place, a 47,500 sq ft building at the 123-acre estate.
Construction is due to start in February.
MEPC Birchwood Park's MD Jonathan Walsh said: "The commitment to build 305 Bridgewater Place represents both a new and exciting phase of activity and a massive vote of confidence in what we can offer here at Birchwood Park.
He added: "This is one of the only major pre-lets in the regional property market so far this year and enables us to forge ahead with the completion of Bridgewater Place which has been the most successful new office scheme in the North West with occupiers including the Department of Work & Pensions, Halcrow, GB Oils, Electricity North West and David Wilson Homes."