Scottish consumers made five million complaints about products and services last year, according to a survey.
The number was up by 38% on the previous 12 months and made Scots more likely to complain than consumers anywhere else in Britain.
However, despite four in five unwilling to put up with poor customer service, there were still 6.2 million complaints not acted upon.
The figures were contained in the second annual Scottish Consumer Action Monitor compiled by Ombudsman Services to track the number of complaints across Scotland.
In total, there were 5.1 million made last year, up from 3.7 million on the previous figure, it said.
They refer to actioned complaints – those that were taken to the supplier, shared on social media and/or escalated to a third party.
A breakdown of the data showed Scots made an average of 1.25 complaints each last year, in comparison to just 1.08 complaints per head in the rest of the Great Britain.
About half (51%) of consumers took action when they had a problem, up from 41% last year and much higher than the British average of 43%.
It found the most common sectors for complaints were retail, energy and telecoms.
Chief Ombudsman Lewis Shand Smith said: “Complaints increased by 1.4 million from this time last year, which is testament to Scottish consumers’ growing awareness and desire to be treated fairly by big firms.
“Despite this positive news, consumers are still ignoring millions of problems each year because they’d rather suffer in silence than go through the perceived hassle of complaining – but it’s not as complex and time-consuming as they might think.
“Consumer rights have been thrown into the spotlight this year and forward-thinking companies are starting to sign up to alternative dispute resolution services, which are free to their customers – with the continued increase of social media, a poorly-handled complaint could significantly damage both their brand and reputation.”
Ombudsman Services commissioned ICM research to carry out the survey of 2,355 people throughout Britain, with 532 questioned in Scotland.