Bruntwood has agreed a deal with outsourcing specialist Bosch Communication Center at The Plaza on Old Hall Street.
Bosch will take 16,500 sq ft on the eighth floor, relocating from a 10,000 sq ft suite in Bruntwood's Cotton House on the same street.
The Plaza has undergone an extensive redevelopment since Bruntwood acquired the building in 2003. Among the £24m investment into the building is the £2.4m reception entrance relocation to St Paul's Square.
The letting means that The Plaza is now more than 85% occupied, with circa 45,000 sq ft of refurbished space available to lease.
DTZ, CBRE and Matthews & Goodman are the retained letting agents for The Plaza.
David Seddon, head of sales at Bruntwood, said: "This letting was one that was strongly contested in the market and it's testament to our flexible approach and commitment to providing the right office solutions for prospective and existing customers that we have secured this lease.
"We recognise that customer's business circumstances will change, whether it's downsizing or in Bosch's case, growing, and as a property partner our focus is on offering real flexibility and enabling customers to move across our portfolio."
John Milburn, general manager at Bosch Communication Center UK, said: "We were looking contact centre space that represented a high quality environment for our employees and customers.
"As an existing Bruntwood customer, we're pleased to continue this relationship at The Plaza, which offers us a high-standard, modern solution that meets our specification demands."
Bruntwood owns 900,000 sq ft across nine major office buildings in Liverpool city centre, including Oriel Chambers and Cotton Exchange. The family-owned company specialises in flexible leases across its property portfolio. Bruntwood offers offices from 125 sq ft upwards with flexible letting lengths and suite specification.
Bosch Communication Center, a business area of Bosch Security Systems, is an international service provider that offers innovative solutions in the field of Business Process Outsourcing. Some 5,000 associates in Europe, Asia and South America provide services and optimize business processes in more than 30 languages.