If you submit your timesheets on a client portal, please follow the below deadlines:
Payment Period Invoice and timesheet approval deadline Funds received
October 2019 4th November 2019 - 5pm Monday 15th November 2019
Week endings to be submitted: 6th, 13th, 20th, 27th Oct & 3rd Nov (5 weeks)
November 2019 2nd December 2019 - 5pm Monday 16th December 2019
Week endings to be submitted: 10th, 17th, 24th Nov, 1st Dec (4 weeks)
December 2019 30th December 2019 - 5pm Monday 15th January 2020
Week endings to be submitted: 8th, 15th, 22nd, 29th Dec (4 weeks)

N.B. Payment calendars are issued in three months rolling blocks - these dates may be subject to change.


Please note expenses must be submitted within two months of being incurred. Any expenses submitted outside of this period may result in non- payment.

Expenses must adhere to the client’s expense policy and all claims need to be accompanied with copies of all corresponding receipts.


Timesheets must be submitted and approved in line with the deadlines reflected in the payment calendar above.  Please note that any late approved timesheets will not be included in the monthly payroll but will be paid later in the month.  

You may be required to send in screenshots of the approved timesheets to timesheets@hydrogengroup.com. Please check the payment guide sent on your original offer email for instruction, if you require a copy of the guide please contact contractorcare@hydrogengroup.com

Self bill

  • Hydrogen operates a Self Bill payment process for contractors. This means that you do not need to send an invoice with your timesheet or expense claim as we will produce an invoice on your behalf and email it to you.
  • Self Bill is fully HMRC compliant, helps to reduce payment delays and is a common practice within the recruitment industry (you may have contracted this way previously). 
  • As part of the onboarding process you will be asked to sign a Self Bill Agreement which may be included in your contract.
  • Please note that if you are paid via an Umbrella Company, we will be asking them to sign the Self Bill agreement as they send us the invoice.
  • If you have any questions, please email selfbill@hydrogengroup.com


Contact information

For all contract related enquires please contact our contractor care team:

For all timesheet submissions and pay related enquiries please contact payroll: