Passing payment processing fees onto attendees
Each business owner has their own preference about how they wish to cover payment processing fees. You can choose to cover the fees or have your customers (event attendees) cover the fees. Covering the fees yourself as a business owner just means that you consider it as part of the cost of doing business. Having your attendees cover the fees means that you either slightly increase the cost of the event to account for the processing fees or make the processing fees an additional cost on top of the event price. The first option masks the fees and bundles them as part of the event cost, while the second option exposes them and makes them an extra cost.
You need to decide which option is best for you — your business and your clients. If you choose to pass the payment processing fees onto your attendees, this help doc explains how to do it and account for Corsizio's flat service fee and Stripe's credit card processing fees.
Option 1: Mask the fees, and bundle them as part of the event cost
This is the preferred choice if you think your attendees may be discouraged from registering to your event if they see an extra cost. To do this you need to raise the price of the event by the amount needed to offset the payment processing fees. It is up to you whether you inform your attendees in the event description write-up that "the event price includes online payment processing fees", or not, depending on what is best for your business and audience.
Here is the formula that you would use, as an example, with Corsizio's $1 service fee and the US and Canada Stripe rates of 2.9% + $0.30 credit card fees:
Total price that should be charged = (funds you want + flat service fee + flat credit card fee) / (1 - credit card percentage rate)
Here is how this looks like on a practical level if your event is $500, and you want to ensure that you receive this full amount in your bank account after service fees:
Total price that should be charged = ($500 + $1 + $0.30) / (1 - 0.029) = $516.27
Therefore, you would charge $516.27, or round up or down depending on your preference, to present your attendees with a round number like $515, $517 or $520.
You will notice that this amount is slightly more than the $500 plus $14.80 if you would do a straight-forward calculation, as you must keep in mind that the fees in this case need to be adjusted in a way that gives you the full $500 in the end.
Option 2: Expose the fees, and make them an additional event cost
This allows you to collect a required fee that you set on top of the event price, and have it be added to your attendee's total charge during the online registration process. This is accomplished with the add-on feature in Step 2 — Pricing & Payment when creating or editing your event. There, you have an option to enable "Include add-ons on top of the above cost" and make it a required add-on, as opposed to optional. You can name this something like "Registration Service Fee" or similar, and ask for your required amount.
Here is an example of what this would look like on your registration form:
Note: This add-on will apply to all of your registrations whether they are done online by your attendees or you enter them manually yourself.