"Realistically we are saving a lot of money," he said.
Mr Allingham believed the three councils were probably sharing more services than any other region in New Zealand.
He said the amalgamation issue had prompted them to look at region-wide services.
"Everybody's looking at how we can save money."
He said if the Local Government Commission ended up amalgamating the councils, they would already have a standard across the board which could make it easier to join up.
Sharing services also makes it easier for people to get good customer service, he said.
It was also good for civil defence teams in emergencies.
"They only have to deal with one contractor, it's a lot easier."
Mr Allingham said it provided stability for contractors, knowing they have an income for a set amount of time.
As well as roading, SWDC also shares contracts for street lighting and rubbish collection with the other two councils.
With Carterton District Council, it shares a contract for footpaths, which was awarded to Higgins, formerly known as Oldfields.
Creating new footpaths is a popular issue with several requests from submitters to the council's the draft annual plan process.
SWDC also works with Carterton to share library services and e-waste management.
Mr Allingham said while the Martinborough Town Hall project was a popular issue to debate, water supply was also big project for the council.
He said the Ministry for the Environment had given them $900,000 for new water bores in Featherston and Greytown.
The contract for highways was still up for tender, he said.
Funding for Cape Palliser Rd, which is expensive for the council to maintain, is still up in the air.
"We are still discussing with NZTA how the funding might work."
