The MSP will make the pledge in her keynote address to the Scottish Labour conference in Perth.
Ms Dugdale believes new taxes would not be necessary to pay for the plan.
She will advocate changes of approach such as ditching SNP plans to cut air passenger duty and Tory proposals to raise higher rate tax thresholds.
Ms Dugdale will say that parties in Scotland must "get serious" about what they would do with the major new tax and welfare powers coming to the Scottish Parliament.
The MSP reckons the restoration of tax credits could be achieved by making different choices in government.
At the Holyrood election in May next year, the Scottish Labour Party will be defending the 38 seats it holds.
Ms Dugdale will tell her conference that a vote for her party would offer a break from Tory austerity.
She will add: "Scottish Labour will stand for the elections with a promise to restore the money Scottish families will lose from this Tory tax rise on working families.
"We will act as soon as the new powers make it possible. We don't need to tax ordinary Scots more to make this change.
"We just need to make different choices from the Tories and the SNP."
The Scotland Bill, currently going through the UK parliament, will contain new powers for Holyrood, including;
On the first day of the three-day conference Labour's UK leader Jeremy Corbyn urged voters in Scotland to back a "left wing alternative" at next May's Holyrood election.
Mr Corbyn also said it was right that decisions about the party north of the border should be taken by members and activists in Scotland.
He has signed an agreement with Ms Dugdale pledging a more autonomous structure.
Who would join Scottish Labour - a party with just one MP north of the border and a poor showing in the polls?
Five young people - attending the Scottish Labour conference in Perth - tell BBC Scotland political reporter Philip Sim (@BBCPhilipSim) what's making them stick and not quit.
A future Labour government at Holyrood would restore tax credits for working families, its Scottish leader Kezia Dugdale will tell party members.