The Department of Parliamentary Services and Anglicare broke the news to parent representatives at meetings on Monday.

The department confirmed in a statement that contractual arrangements with the existing provider would finish at the end of the year.

The move follows lobbying from all sides of politics as well as involvement from the Assistant Minister for Education, Sussan Ley, to ensure continuity of the service after the pullout was flagged in July.

Anglicare has cited problems with making the centre financially viable, saying it would need more space in the house to accommodate three to five-year-olds.

In the statement DPS secretary Carol Mills signalled the new tender would not expand the age group of the children, asking for providers to offer services for children aged six weeks to three years.

Ms Mills also said new providers would have to provide modelling and evidence they could keep the centre financially viable "over the life of the period of the agreement".

Providers who offered services for children aged three to five years close to Parliament House would also get preference, the statement said.

In the meeting, the department said it was "optimistic" that a new provider would be announced by the end of September or in early October. Either way, parents would be informed by September 15.

ACT Anglicare chief executive Jeremy Halcrow said the department was effectively re-tendering the same model, so it would not be tendering.

"From our perspective we are very disappointed we have been unable to renegotiate an expanded preschool model for Capital Hill which we believed to be the most viable option," Mr Halcrow said.