Louise Iona Matheson McMillan (born 27 July 1997) is a Scottish rugby player from Glasgow.

She was in the Scotland Women 7s squad, which won the Rugby Europe Trophy in 2015 to gain promotion to the Grand Prix competition.

[9] She was "sin binned" in the match against Italy in the closing minutes for collapsing a maul that was creeping towards the line and that resulted in a penalty try.

Before beginning her studies, she took a year out and worked at law firm Pinsent Masons, balancing this with her rugby commitments for the Scotland under-20s squad.

[8] She completed her law studies at Glasgow during the COVID-19 pandemic and has spoken about her experience of playing international rugby while being at university, saying: "I went into halls of residence, but I was not really living the ‘freshers’ lifestyle at all, I was first to bed and first to get up - it was worth it all when I earned my first full Scotland cap against Spain though [in November 2016].