It is not permissible for the vendor to charge extra to the one who makes late payments

Is It Permissible to Take Riba-Based Loan for a Need?

This is the essence of ribaa

Ruling on buying a mosque with an interest-based loan

Lender referring a third party to debtor for extra money

He wants to bring in a person to take his place in a ribaa-based investment bank account to save himself

Is it permissible to deal with ribaa in a ribaa-based society?

Helping people to buy used cars with ribaa (interest)

Using something which was bought with ribaa

Ruling on taking ribaa from deposit accounts in kaafir banks