Splitwise itself does not charge a fee when you use our PayPal, Venmo, and Paytm integrations.
However, these partners may charge you a fee in certain scenarios. For example, as of 2019-02-06 Venmo charges a 3% fee if you fund your payment with a credit card.
If you have any questions about these fees, please research our partners' policies using the links below.
PayPal (USA): https://www.paypal.com/en/webapps/mpp/paypal-fees#sending-friends-family
Venmo (USA): https://venmo.com/about/fees/
Paytm (India): https://blog.paytm.com/how-to-send-money-using-paytm-1424e8218141