The MP for Moray had referred himself to the Standards Commissioner last year.
Mr Ross referred himself to the Standards Commissioner in November for not recording his full MSP salary and earnings as a match official for the Scottish Football Association.
In a judgment released on Friday, Parliamentary Commissioner for Standards Kathryn Stone said the MP for Moray did not intend to deliberately mislead the public by his omission, and said she was satisfied that the matter had now been dealt with.
Ms Stone also noted Mr Ross had “since implemented new procedures to stop these failings reoccurring.”
It is understood the MP failed to declare £28,218.57 in outside earnings from his second job as Highlands and Islands MSP and third job as a football referee.
The undeclared income included £6,728.57 from 16 football matches in 2021 and 2020, and £21,490 in a top-up salary from his role as an MSP.
Following the judgment, Mr Ross said he had “accepted full responsibility for getting this badly wrong”.
He said: “As soon as I realised this error, I provided the UK Parliament with all relevant details, and reported it myself to the Parliamentary Commissioner for Standards.
“I also apologised at the outset for making this mistake and accepted full responsibility for getting this badly wrong. I want to repeat that apology today and guarantee that it won’t happen again. I have taken steps to stop these failings occurring again.
“My MSP salary continues to be donated to charity and has been declared on time since November, as will any future payments received for football games.”