MULTI-STATE: Online retailers will have a few changes to their sales tax laws if the Marketplace Fairness Act is approved. A bipartisan group of senators introduced the bill on Tuesday (3/10/15). The Marketplace Fairness Act of 2015 would give states the option to require out-of-state businesses, such as those selling online or through catalogs, to collect and use taxes already owed under state law the same way local businesses do. It relies on the Streamlined Sales and Use Tax Agreement among states.