Credit scores can technically change any time there is a change in your credit reports. A credit score is simply a calculation based on a snapshot of your credit report when it's pulled.
Most of the time your accounts like credit cards, installment loans, or mortgage loans will update their information every 30 days. Each account as a specific reporting date during the month. Negative items such as collections or judgments can pop up at any time. Thanks! Heather with BoostMyScore.NET