The Sun is raising its cover price by 10p on Saturdays and by 20p on Sundays.
The moves means that The Sun on Saturday will now cost 70p and The Sun on Sunday will be £1 (the same price as the News of the World, which sold 2.6m copies a week when it was closed down in 2011).
The Sun on Sunday today also announced the signing of former French international Thierry Henry as a football columnist, starting this week.
More “enhancements and expanded sections” are to be announced “shortly”.
The Sun sold an average of 2,240,862 copies a week on Saturdays in February and 1,489,942 on a Sunday, according to ABC.
Sales of The Sun fell 10.1 per cent year on year in February (versus a 6.6 per cent decline for the Daily Mirror). Sales of The Sun on Sunday fell 12.1 per cent (versus 8.7 per cent for the Sunday Mirror).
News UK noted today that The Sun on Saturday remains cheaper than the Daily Express (85p), Daily Mirror (90p) and Daily Mail (90p).
The Sun on Sunday remains cheaper than the Sunday Mirror (£1.20), Sunday Express (£1.40) and Mail on Sunday (£1.50).
Annual weekend sales of The Sun are said by the publisher to generate sales of £158m, with £33m of that going to retailers.
Chief marketing officer of News UK Chris Duncan said: “As Britain’s best selling newspaper, The Sun reaches over 10.5m readers every week. As well as the attraction of high sales and good margins from our titles, the weekend editions support retailers in securing customer footfall and the benefits of additional basket spend.
"Our new weekend pricing and terms to the trade will now bring us in line with the majority of the best selling weekend titles. The changes will also support the continued investment News UK is making in its print products, helping retailers to enjoy growing sales value and better cash margins."