There are no fees on cash/checks. You are able to add all cash/check donations for free.
This will help you track all donations as you can add a cash/check donation directly to a participant or your main campaign (e.g. a check from a business sponsorship).
As a reminder, 99Pledges is Free to use. The only fee is the credit card transaction fee charged by the credit card companies.
How to add cash/check donations: https://help.99pledges.com/en/articles/690265-how-do-we-enter-cash-checks
We understand accepting cash/checks is another option to give donors, but we recommend you strongly encourage donors to first use the platform to make a donation. There are many benefits to having all donors make their donation through 99Pledges:
Donors give 25% more online than through cash/check (well above the ~3% processing fees charged by PayPal/Visa/MC/Amex)
Donors can see goals and standings which motivates them to donate more (potentially even multiple times)
Donors can easily spread the word through the one-click sharing buttons
And finally, the biggest benefit we'd say, it's a lot easier on you (as the Admins) to manage and track