The Principality Premiership kicks-off two weeks into the rugby season, with the British & Irish Cup qualification games taking place on the first two weekends of September. Following on from Llandovery v Cardiff on the opening weekend of league action, S4C's cameras then move to St Helen's to capture Swansea v Neath on Sunday, 22 September (2.30pm).
Current champions Pontypridd take on Newport on Sunday, 29 September, the next game to be aired live on the channel (2.30pm), with Bedwas v Llanelli on October 6 taking place at 4.15pm.
WRU Group Head of Compliance Julie Paterson said: "The WRU is delighted that S4C have scheduled these excellent opportunities to showcase the Principality Premiership to a live television audience here in Wales.
"The Principality Premiership is growing year on year in terms of the standards on and off the field and the sequence of televised games across consecutive weekends will build support for these teams and give the players and coaches the visibility they deserve.
"A tremendous amount of work has been done over the past few years to ensure the Principality Premiership is a force to be reckoned with as it plays a crucial role in Welsh rugby's performance pathway for elite players.
"For S4C to recognise the importance of the league in this way is a fillip to the players and coaches and a reminder to all Welsh rugby fans that Principality Premiership rugby is a great asset to the game here in Wales."
Llion Iwan, S4C Content Commissioner, said: "We are proud to include live Principality Premiership games as part of S4C's coverage for the 2013/14 rugby season - which features Welsh rugby on all levels: from international tournaments, to Regional and Club level, and on to the grassroots of college and schools rugby."
Graeme Yorston, Chief Executive of the Principality Building Society, commented: "As long term sponsors of the Principality Premiership and as broadcast sponsors of the rugby coverage on S4C we are absolutely delighted that these matches are being shown live.
"The level of rugby played in this league, which is undoubtedly the breeding ground for the stars of the future, is excellent and I am sure that the viewers as well as the clubs themselves will enjoy the experience."
Confirmed S4C live Principality Premiership matches:
15/9/13 Llandovery v Cardiff 14.30
22/9/13 Swansea v Neath 14.30
29/9/13 Pontypridd v Newport 14.30
6/10/13 Bedwas v Llanelli 16.15