The first wave of ballots for British Columbia's referendum on the harmonized sales tax were sent out by mail Monday, despite a rotating postal strike.

Elections BC spokesman Don Main said HST referendum voting packages for next month's mail-in referendum were sent to residents in 38 B.C. electoral districts in northern B.C., the Interior and the Islands.

Voting packages for the remaining 47 electoral districts in the Metro Vancouver region will be in the mail starting next Monday, he said.

Elections BC is mailing more than three million packages to B.C. residents, who will decide the future of the HST.

"The voting packages consist of a ballot, instruction sheet and three envelopes that are required in order for voters to cast their ballot," Main said.

Ballots must be received by Elections BC before 4:30 p.m. on Friday, July 22 to be counted in the vote.

Main said Elections BC has the legal authority to extend the voting period if the ongoing Canada Post strike disrupts the mail-in voting, but it's too early to consider any such action.

"Elections BC has been in constant contact with the officials at Canada Post and so far, we don't see that it's affecting the referendum at any time," he said.

The combined tax was introduced by the Liberal government in July 2009, on the heels of a provincial election that made no mention of the tax, and has been law in B.C. since July 1, 2010.

A successful petition campaign led by former B.C. premier Bill Vander Zalm forced the referendum under the province's direct democracy laws. The laws, unique to B.C. in Canada, allow voters to mount petition drives that can force byelections to recall politicians or hold provincial referendums or political votes to overturn some laws.

More than 500,000 British Columbians signed the petition last spring calling for the repeal of the HST.

The referendum question asks: "Are you in favour of extinguishing the HST (Harmonized Sales Tax) and reinstating the PST (Provincial Sales Tax) in conjunction with the GST (Goods and Services Tax)?"

Critics say the referendum question is confusing, but Elections BC says the vote is straight forward. People who want to dump the HST will vote "yes," while those who support the tax will vote "no."

"The ballot is very clear, there's a yes and a no circle beside the question on the ballet, and voters can read the question and make their choice," Main said.

Both pro- and anti-HST camps are now busy trying to woo voters with town halls and advertising campaigns.

Opposition New Democrat Leader Adrian Dix took his anti-HST campaign to the Vancouver Island communities of Courtenay and Campbell River where he said he wants to build excitement about the opportunity British Columbians have to dump the tax.

Dix said he wants British Columbians to know that a yes vote in the referendum will help kill the tax.

"Part of it is sending that strong message that it's a yes vote that's needed," he said. "That that's the vote that gets rid of the HST."

Premier Christy Clark will discuss the benefits of the HST and the voting process at a meeting Tuesday in Richmond.

The government says the combined tax spurs investment and job creation, but opposition groups say it shifts $2 billion in taxes from business to consumers.

Former premier Gordon Campbell announced his early retirement last November, saying his personal unpopularity over the unrolling of the HST was holding back his government's ability to govern.

Clark, Campbell's successor, has promised to drop the combined federal-provincial tax to 10 per cent from 12 per cent by July 2014, if British Columbians vote to keep the HST and Ottawa amended federal regulations last week permitting the reduced HST rate.

The results of B.C.'s mail-in referendum are expected in late August.