First, a few words about the basic math
Unemployment taxes are calculated on each worker’s taxable wage base, and the tax rate schedule is determined by your state. State UI taxes are calculated by multiplying the taxable payroll by the state tax rate.
In Missouri , for example, the state unemployment insurance program assigns each new employer a new employer rate. Employer tax rates are set based on an industry classification. If a particular industry has a high level of unemployment claims, the new business UI tax rate will be relatively high.
After several years, Missouri assigns an experience rating to the employer’s account. The UI tax is based on the dollar amount of payroll, unemployment benefits paid to former employees, and the firm’s voluntary payments into the state unemployment trust fund.
You can reduce your state unemployment tax by lowering your rate of employee turnover, and by minimizing the number of former employees who file for unemployment benefit payments during the calendar year.
Here are more details on lowering your unemployment insurance contribution rate.