Federal Labor would introduce its changes to negative gearing and capital gains tax by January 1 next year if the party wins the May election.

The negative gearing reforms won’t apply to newly-built homes and existing investment properties, while the capital gains tax discount will be halved for investments entered into after January 1.

Shadow treasurer Chris Bowen says the property tax changes will raise $2.9 billion over the forward estimates.

“If you already use negative gearing, nothing changes. It’s not retrospective. And you can still use it for new houses,” he said in a statement on Friday.

“Federal Labor’s plan is good for the budget, good for housing construction jobs and fair for first home buyers.”

Labor also announced it would cut the managed investment trust withholding rate in half, from 30 per cent to 15 per cent, to encourage new housing.