Mizanur and Sadiqur Rahman pocketed £240,000 VAT that should have been paid on the sale of two restaurants they ran in Stafford and Lichfield.
The duo together with Mohammed Uddin and Abdul Kamal - all directors of the controlling company - also plundered a further £200,000 with business partners Mohammed Uddin and Abdul Kamal through lying about their takings at the Panache in Birmingham Road, Sutton Coldfield, and using the significantly reduced bogus figures to illegally cut their Corporation Tax, Income Tax and National Insurance bills.
The four crooks also trousered a further £295,000 by claiming tax credits based on the artificially reduced income for ten years before the racket was uncovered by an investigation triggered by their failure to pay VAT on the restaurant sales, Birmingham Crown Court heard.
When Revenue and Customs officers arrested the quartet in connection with that tax fraud in 2015 they uncovered far more dishonesty.
Paper and computer records recovered from the Wednesbury homes of 44-year-old Mizanur Rahman and Uddin, aged 48, revealed the men and their two colleagues had secretly syphoned cash from the Panache.
Two financial record books were kept but the 'official' one - signed off by the four directors and their unwitting accountant - only included credit card sales at the restaurant. These figures were the basis for the tax frauds.
The other book revealed the true picture in which cash payments from customers - around £7,000-a-week including hundreds of pounds of staff tips - were skimmed from the profits and used by the four men to increase their own incomes without disclosing the boost to the taxman.
Sentencing at Birmingham Crown Court on Friday, Recorder William Edis QC said: "This was an extensive, planned and prolonged tax fraud.
"You systematically, regularly and frequently under declared sales at the Sutton Coldfield restaurant and kept shadow books that showed the true picture.
"These frauds took place over six years with the creation of a bogus paper trail. It was sustained and planned. You are all equally guilty of these offences.
"All of you are of good character, you all appear to be respected members of your community. You all have dependent relatives, all older and in some cases younger. You are, in short, hardworking family men."
Mizanur Rahman splashed out money on luxury holidays in Florida, Mauritius and Dubai.
Rental properties were bought locally by the men who also claimed that over £175,000 of the money had either been invested in a failed Bangladesh project or sent to family members.
Uddin from Holyhead Road, Wednesbury; Abdul Kamal, 41, of Brandon Close, West Bromwich; Mizanur Rahman from John Wesley Way and his 45-year-old brother Sadiqur from Churchfields Road, both Wednesbury, each admitted cheating the public revenue between 2009 and 2015 and knowingly under declaring income to obtain tax credits from 2005 and 2015.
The Rahman brothers were put behind bars for three years and banned from acting as directors for seven years while Mohammed Uddin and Abdul Kamal each received a two-year suspended jail sentence and banned from being a company director for five years.
Revenue and Customs officers have so far recovered £538,000 from the defendants with proceeds of crime proceedings to follow.
Richard Mayer, Assistant Director of the Revenue and Customs Fraud Investigation Service, said: "These fraudsters abused the tax system in a cynical and systematic way to help fund their lifestyles.
"They took money intended for staff and deprived public services of vital funding by stealing from the taxpayer. They are now all paying the price and we will be taking the money back from them."
Tips about tax fraudsters can be made via the Fraud Hotline on 0800 788 887.