Why Your Credit Score Drops When You Apply for a Mortgage — the Mortgage Score System, Rate-Shopping Rules, and the 2026 VantageScore 4.0 Shift

Why Your Credit Score Drops When You Apply for a Mortgage — the Mortgage Score System, Rate-Shopping Rules, and the 2026 VantageScore 4.0 Shift

Douglas Wilkerson
Published on: 25/09/2026

Your Credit Karma score isn't your mortgage score. A Jacksonville mortgage broker explains mortgage FICO models, the tri-merge middle-score rule, rate-shopping windows, and the 2026 VantageScore 4.0 change.

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