Building has begun on a 13 acre site at Tuscany Park on the M62/M1 junction and is scheduled to finish in June next year.
The factory will serve retailers across Yorkshire and is intended to run alongside the existing Westgate End site, creating 200 extra jobs. It will have four times the production capacity of the existing factory, which makes 4,500 loaves per week.
Warburtons sales director Marc Dubery said: “The new plant will allow us to supply local customers with a lot more products and enhance their freshness. We have built it in line with our aim to fulfil growing customer demand. The current one does not fulfil our projections for demand.
Chairman Jonathan Warburton said: “This is a massive investment and reinforces our commitment to becoming a national brand.”
The move comes after Warburtons’ Wednesbury plant in the West Midlands was devastated by fire in January. The factory is expected to be fully operational by January.