The Pay As You Earn (PAYE) online service will be unavailable from 11:45pm on 5 April 2018 to 8am on 6 April 2018.
The planned downtime is due to scheduled maintenance for the new tax year. Customers are advised that, following this period when the service is unavailable, they will then be able to file expenses and benefits forms for 2018 to 2019.
HMRC has apologised for any inconvenience.
"I have used The Learn Centre on a number of occasions and have found it provides a great platform to gain the knowledge required to carry out my job. I started off with the Payroll Technician course and this in-depth learning gave me a great foundation of payroll knowledge to build upon and give me the confidence to progress up the career ladder, well worth it and would certainly recommend, no matter what level you are at there will be a course/qualification that can help you."
Ayman Zagloul
HR Analyst at Queen's University Belfast