Many firms shy away from the idea of charging interest as being unprofessional or somehow underhanded. However, it is these firms that typically have the longest receivables period. Unless you charge interest, what incentive does your client have to pay you in a timely fashion, other than the risk that you may withdraw from their case? Hmmm… pay the attorney or go to Disney World? And as economic times continue to be forecast as gloomy, clients may put your bills aside and take even longer to pay you for legal services. And, a delinquent client, whose outstanding bills are accruing interest may call and seek some payment term or forgiveness – consider forgiving interest if they pay the principal due sooner rather than later. Yes, interest can be a bargaining chip to not only ensure on time payments, but also persuade a late paying client to catch up on his/her payments to your firm! Having said this, before you begin to charge interest, you should be proactive and ensure that whatever interest rate you charge is within the guidelines of your state or provincial bar rules and regulations, within the guidelines of statutory laws in your state/province and, most importantly, you should advise your client in engagement agreements and on each and every invoice that you send out that unpaid balances are subject to interest at xx rate. Thus, charging interest will certainly make your clients take interest in putting your bills in the pile of bills they intend to timely pay.