Employers must make First Quarter payments of PAYE and NICs by 19 July 2016 if settled by cheque. If you pay electronically, then you have until 22 July to make the payment. Tax retained under the Construction Industry Scheme must also be paid by the same date. Class 1A national insurance due from any P11D return must be paid as well by the same date.
This warning applies to small employers who pay quarterly. Large employers will need to pay monthly. First Quarter means the first three months of the income tax year running from 6 April 2016 to 5 April 2017. This is the quarter running from 6 April 2016 to 5 July 2016.