CLSI accepts online payments using any major credit card, and you will pay a convenience fee of 3 percent in addition to the amount of your charge. The convenience fee is included in the total charge for the transaction. This convenience fee covers costs associated with the transaction.

Debit Cards are not subject to a convenience fee.

Instructions for paying an INVOICE:

  1. Click “Pay Now”. (You will be redirected to our third-party secure website for the transaction.)
  2. Enter your invoice number(s) in the Job or Invoice Number field.

If you are attempting to pay multiple invoices, please make a payment for each invoice number. Or combine multiple payments under one invoice number.

Instructions for paying a RETAINER:

  1. Click “Pay Now”. (You will be redirected to our third-party secure website for the transaction.)
  2. Enter your Project or Proposal ID in the Job or Invoice No. field.