The club reviewed pay rates affecting an estimated 100 full-time employees and hundreds more non-permanent staff whose wages fell below the new living wage threshold.
Celtic staff had been paid £7.85 per hour.
But the rate, adjusted by the Living Wage Foundation, was raised by 40p last November.
Details of the agreement, which came into effect in July, have been revealed in the club’s financial papers.
It comes after the Celtic board faced criticism at last year’s AGM for failing to sign up to the living wage standard.
Chairman Ian Bankier said then it was “not in the interests” of Celtic to follow in the footsteps of around 380 Scottish employers - including fellow Ladbrokes Premiership club Heart of Midlothian - in signing up to the scheme.
Many shareholders called for the club to change their stance with shareholders and fan group, the Celtic Trust, supporting a resolution that the board take “all necessary steps” to make Celtic an accredited living wage employer and to provide to shareholders a progress report on this within three months.
The fan group had also been concerned about the withdrawal of a discretionary bonus system for staff receiving the living wage rate.
The supporters’ group said at the time that it was “penny pinching of the worst kind” and it appeared the club had been “trying desperately” to find ways to do the “absolute minimum”.
It has now been confirmed that the minimum rate hourly rate of £8.25 a hour was implemented from July 1, “reflecting the prevailing voluntary living wage rate”, although there is no indication of a change in position over becoming an accredited employer.
Details of the living wage increase came as it emerged board of directors’ overall salary costs rose by 20 per cent in the last year due largely to a near-£240,000 ill health payment to long-serving former financial chief Eric Riley.
The Parkhead club had previously said it would not sign up to the living wage scheme as it would mean “handing over decision making on salaries to another agency”.
The Celtic Trust has said that, as “progress has been made - small though it is”, that it will not be bringing a living wage resolution to the forthcoming annual general meeting, the date of which is yet to be decided.
But it said it had not abandoned its campaign and would continue to bring pressure to bear on the club to become fully accredited living wage employers.
In a message to supporters, the Celtic Trust said: “The lowest paid workers have now been paid more than they would have been without this campaign and we are delighted about that.
“We hope you will continue to support us, and that, unless national political developments overtake it, we will soon be able to say that our club is an Accredited Living Wage employer.
“We think Brother Walfrid would have wanted that, don’t you?”
Celtic Football Club was formally constituted at a meeting by Brother Walfrid on November 6, 1887, with the purpose of alleviating poverty in the east end of Glasgow by raising money for the charity he had instituted, the Poor Children’s Dinner Table.