The airline and operator will put on a total of 14 additional breaks in February and March next winter from Leeds Bradford and Newcastle airports in response to an uptick in demand.
As a result of the expansion, the companies will operate their biggest ever programmes to Iceland, with flights and city breaks departing from all 10 of their UK airports next year.
The programme now represents more than 150 departing flights and more than 30,000 seats on sale, meaning a capacity increase of 36% compared to last winter.
Seven weekly departures have been added from Leeds Bradford owing to new Sunday services operating between 11 February and 27 March.
Elsewhere, seven weekly departures have been added from Newcastle thanks to new Wednesday services operating between 7 February and 24 March.
A programme of flights will also operate from Manchester and Birmingham in winter 2023/2024, with two weekly flights (Monday and Thursday) operating in late-September, October, November, February, March and April.
Steve Heapy, chief executive of Jet2.com and Jet2holidays, said: "We have continued to experience strong demand for flights and city breaks to Iceland from customers and independent travel agents, so we are very pleased to be expanding our programme today in response.
"This means we have our biggest ever programme on sale to Iceland for winter 23/24, and the natural wonders of this magnificent destination, coupled with our award-winning product, means we expect these new flights and breaks to sell very quickly."
