Tasmanian's political leaders have left their future in the hands of voters after casting their ballots in the state election, with Premier Will Hodgman admitting to nerves "a little like a wedding day".

Mr Hodgman was joined by wife Vicky and their children at a Sandy Bay primary school on Saturday morning where he bypassed a sausage sizzle on his way to the ballot box.

Labor Opposition Leader Rebecca White and Greens Leader Cassy O'Connor cast votes in their home electorates.

Even the busiest polling booths in the Apple Isle don't attract the fanfare of other states, with Tasmanian laws preventing party advertising and how-to-vote cards.

The restrictions also extend to publishing details about policy or political analysis.

Sitting on a school bench to pat a mate's dog named Daisy, Mr Hodgman said said the mood was "a little like a wedding day, just waiting for the big moment later in the day".

"There's always a few butterflies on a day like today, but you know that's part and parcel," he said after stopping to buy some cookies.

"There's a lot riding on it, not just for me and the team, but for our state."

Ms White cut a relaxed figure alongside husband Rod and daughter Mia at Sorell Memorial Hall in Lyons.

At age 35, she could become the youngest premier in Tasmania's history.

"I'm very optimistic because we've run a very positive campaign talking to people about the things they care about," Ms White told reporters.

"I hope today that with our candidates, that have worked so hard across the state... that we can win."

The Liberals hold 15 seats in Tasmania's 25-seats lower house.

With 13 seats needed for majority government, Labor needs to add six to their 2014 total of seven.

Seeking a second term, Mr Hodgman wouldn't be drawn on what the Liberals would do in the event of a hung parliament.

Ms O'Connor described the 2018 poll as a "a battle for Tasmania's soul" and the island's clean, green future.

The Greens are hoping to pick up an extra seat but are at risk of losing one of three they already hold, the northern seat of Bass in Launceston.

Ms O'Connor would not be drawn on whether she may need to wait by the phone on Sunday should neither Liberals nor Labor win majority government.

"We won't know what the actual result is until the final count's in and that can take some days," she said in West Hobart, in the seat of Denison.

Roughly 330,000 Tasmanian are expected to vote throughout the day before polls close at 6pm (AEDT).

Around 50,000 people have already pre-polled, the Tasmanian Electoral Commission says.

© AAP 2018