If you cross the 520 bridge without a Good to Go pass, keep your eyes peeled for the bill. You could easily miss it.
Toll bills are being mailed in plain white envelopes with no marking that say a toll bill is inside or that it's from the Washington state Department of Transportation.
Some people have mistakenly thrown them out.
State officials say if drivers don't pay the toll bills delivered in the mail, they may face civil penalties. For every bill that goes unpaid, drivers face a $5 fee for every reminder bill. And if it goes past 80 days, drivers face a $40 civil penalty.
WSDOT says they're keeping an eye on the issues surrounding the tolling envelopes.
"We are monitoring the situation," said Craig Stone, WSDOT. "The question is, should we put stickers or stamps on them. We're going to be able to work through envelopes we have. Our next order, we'll consider putting Good to Go on them ... It's actually fairly expensive for us to put the stickers onto them. Ask people, just respect the toll bill."
WSDOT is asking drivers to pay attention to your mail. If you cross the bridge and haven't received a bill in two weeks, call WSDOT.
For drivers forking over the money, Stone said they'll soon be able to see what they're getting for their toll. Pontoons will be brought into Lake Washington from Aberdeen and barges will soon be on Lake Washington.
"People will start seeeing the real construction. That's what the tolls are for. They're paying towards a billion dollars to get a new bridge in place and have that improvement," said Stone.
KING 5's Natasha Ryan contributed to this report.