[5][6] In July 2019, Porterfield scored his 4,000th run in ODI cricket and recorded his 50th win as captain of Ireland's One Day International team.

[9] Porterfield made his first-class cricket debut on 17 May 2006, for Ireland against Namibia in the 2006–07 ICC Intercontinental Cup.

In a match against Bermuda as part of the 2007–08 ICC Intercontinental Cup, Porterfield scored 166 runs from 326 balls.

Porterfield said "I've learnt a lot from Trent – he brought young players through, looked after them and he set an example by how he went about his game and how he prepared on and off the field.

[17] A side made up of some of the best players from Associate and Affiliate teams was put together to face England in Dubai in January 2012.

In May 2018, Porterfield was named as the captain of a fourteen-man squad for Ireland's first ever Test match, which was played against Pakistan later the same month.

[31] Porterfield attracted interest from Gloucestershire during the 2007 World Cup and was given a trial with the county in between international commitments.

[34] Porterfield was absent from Ireland's last two Friends Provident Trophy matches as he was called into the Gloucestershire squad, Kyle McCallan took over the role of captain.

[15] He came close to scoring his maiden first-class century for Gloucestershire in a match against Glamorgan County Cricket Club in August 2008 but was out for 93.

[36] On 10 September, he and Kadeer Ali shared in Gloucestershire's highest opening partnership of the season; he scored 66.

In October 2010 he signed a three-year contract with Warwickshire, joining fellow Ireland international Boyd Rankin.