Here is a post about it from 2019, guessing there are others too lazy to look. https://quickbooks.intuit.com/learn-support/en-us/employees-and-payroll/qb-was-notified-in-may-that-...
1. QBO is incorrectly adjusting gross wages for the SIMPLE calculation both sides: the employee and the employer. We have been adjusting this manually since 2018, this adds labor costs. SIMPLE calculation seems to be factoring in adjustment(s) to gross wages & benefits to the employee such as health insurance employee gross wage deduction, HSA gross wage deduction, etc and possibly non taxable items HSA employer contribution.
2. The SIMPLE employer match is a year to date calculation, this has been done incorrectly by QB all versions since I have been working in accounting around 20 years. For example if an employee starts contributing (this employee has been working since January 1st) to the SIMPLE plan in mid-year at 10% of wages and the employer match is 3%. The employee would get a 10% employer match on each paycheck until the year to date employer match reaches 3% of gross wages. Then the match by paycheck would drop to 3% employer.
I am not here to debug QBO/figure what the program is doing wrong. QBO doesn't pay me to figure the fine details. I feel bad for individuals using QB and do not know this is incorrect.
