The minimum contributions were introduced in 3 stages known as phasing.
If the qualifying earnings basis is being used, the minimum contribution until 5 April 2018 was 2% with at least 1% from the employer.
Between 6 April 2018 and 5 April 2019 the minimum contribution was 5% with at least 2% from the employer and from 6 April 2019 the minimum contribution has been 8% with at least 3% from the employer.
For more information see The Pensions Regulator contribution levels guidance.