As tomorrow’s deadline to file taxes nears, small business owners have an unequivocal message for Congress: Reform the federal tax code.

Just released, the 2015 Small Business Attitudes On Taxes survey revealed that 90% of small business owners believe the federal tax code needs reforming. Similarly, 88% say such reform should be a priority for congress and President Obama. About 85% of owners believe effective reform will be very helpful (52%) or mildly helpful (33%) to their efforts to grow their businesses.

“These survey results should be an eye-opener for federal legislators as they come back from the April recess,” said Hari Ravichandran, CEO of Endurance International Group, which conducted the survey. “If we want to keep our economy moving, congress and the White House need to address the concerns of U.S. small businesses. It starts with looking at ways to reform the tax code that enable small business owners to reinvest in expansion and hiring.”

Currently, 88% of owners feel federal legislators fail to adequately take into account impacts on small businesses when considering tax code reforms. That’s especially worrying because 73% of survey respondents said that federal taxes are more concerning than state and local taxes. The top gripes business owners have with the taxes handed down from Washington D.C. are that they are too high and too confusing. There are also too many taxes, which makes it difficult to keep track of tax obligations, owners say.

With web and mobile commerce expanding rapidly, some 63% of owners additionally said they are concerned with the issue of online sales tax. About 80% of survey respondents believe that businesses with less than 50 employees should be given exceptions from online sales tax. Interestingly, 55% of respondents feel there should be no online sales tax at all. About a quarter of owners think online sales should be taxed, but only in the state where the business is located. Only 7% of respondents think the sale should be taxed in the state where the business is located and where the consumer is located.

A technology provider of cloud-based platform solutions, Endurance International Group conducted its survey of 827 U.S.-based small businesses from March 27 to April 7.