UPI per transaction, per day limit: HDFC Bank, SBI, ICICI Bank, YES Bank, Kotak Mahindra Bank, PNB, Canara bank
UPI is built over the IMPS infrastructure and allows you to instantly transfer money between any two parties' bank accounts. If you send money to another individual, there is a limit on per transaction and per day limit set by NPCI and also in some case by banks.