Four million Americans want to leave their union, but either they don't know that they can or they don’t know how to do so. For many of them, now is the time to act: August is opt-out month for many unions nationwide.

This number comes from a just-released Google Consumer Survey poll that shows more than 28 percent of union members would like to leave their union if they could do so without penalty. That’s about 4 million of the nation’s 14.5 million union members.

It's not surprising that millions of employees want to leave their unions. Many wonder why they should pay for their union’s lousy customer service.

Some dislike paying dues that can top $1,000 a year, the price of a family summer vacation or a mortgage payment. Others don't want their dues to support political causes or the lavish salaries of many union bosses.

What's amazing is that these 4 million dissatisfied union members already have the right to leave their unions without penalty, even if they live in states without right-to-work laws.

In the 24 states with right-to-work laws, employees can leave their union and aren't forced to pay dues to a union they don't belong to.

In the other 26 states, union employees can still opt out of union membership and receive a rebate for the portion of their dues that goes to political spending.

Or they can become a religious or conscientious objector and redirect their dues amount from the union to a charitable organization.

Few union members know they have these options, however, and union bosses typically make it even more difficult to leave by allowing employees to opt out only during certain little-publicized times of the year.

In many states, teachers are only able to leave their union by opting out in August. In some places, teachers only have a two-week window to leave their union, even though they can join at any time.

This is what happened to Rob Wiersema. After Michigan passed a right-to-work law in December 2012, Wiersema tried to leave the Michigan Education Association in June 2013.

In July, the union charged his credit card for union dues, because MEA says teachers can only leave in August.

This is why a grassroots coalition of 70 groups in 41 states has come together to celebrate National Employee Freedom Week.

From Aug. 10 to 16, these groups will sponsor a series of events, advertisements and outreach activities to let union employees know about the freedoms they have to leave their unions.

From efforts in Washington state and Connecticut to let home care providers know they can leave their union, to mailing information to teachers in Louisiana and Illinois about the options they have to drop union membership, this coalition will inform more union members than ever about when and how they can leave their unions.

The overwhelming majority of the public supports this right-to-work principle. According to another Google Consumer Survey poll released by NEFW, 83 percent of Americans agree that employees should “have the right to decide, without force or penalty, whether to join or leave a labor union.”

Polls show that union members want to opt out of their unions and that the public thinks that they should be able to do so. NEFW lets them know they can leave and helps them understand how it’s done.

And though some opt-out windows are only a few days long, the infrastructure built up by NEFW this week will help ensure that workplace freedoms are highlighted year-round.

Victor Joecks is executive director of National Employee Freedom Week.