The one day strike was the second in a planned series.
Unison says the 2.5% pay offer is below inflation and less than that received by English council workers.
The union is holding out for 5%, but the Convention of Scottish Local Authorities, Cosla, said budgets were already squeezed.
The Scottish finance minister, Jack McConnell, yesterday announced extra funding for local authorities, but the extra money will not help to settle this year's pay claim.
Unison and Cosla are due to meet for further talks tomorrow.