California may be ready to close a usury cap loophole that has allowed some lenders to offer installment loans with triple-digit interest rates.

Legislation that caps interest rates on installment loans between $2,500 and $10,000 at 36 percent plus the federal funds rate sailed through the California Assembly in May and a hearing is set in the Senate on June 26.

Two members of the California Senate’s seven-member Banking Committee, including one Republican, have already pledging their support for the...