diff --git a/packages/primeng/src/inputmask/inputmask.ts b/packages/primeng/src/inputmask/inputmask.ts
index 94fff6ea702..d74ff39060c 100755
--- a/packages/primeng/src/inputmask/inputmask.ts
+++ b/packages/primeng/src/inputmask/inputmask.ts
@@ -498,6 +498,18 @@ export class InputMaskDirective extends BaseComponent<InputMaskPassThrough> {
         return pos;
     }
 
+    /**
+     * Count the number of fixed (non-editable) mask characters in the range [from, to).
+     * Fixed characters are those where tests[k] is null (e.g. separators like '.' or '/').
+     */
+    private countFixedChars(from: number, to: number): number {
+        let count = 0;
+        for (let k = from; k < to; k++) {
+            if (!this.tests[k]) count++;
+        }
+        return count;
+    }
+
     shiftL(begin: number, end: number) {
         let i, j;
 
@@ -507,6 +519,12 @@ export class InputMaskDirective extends BaseComponent<InputMaskPassThrough> {
 
         for (i = begin, j = this.seekNext(end); i < (this.len as number); i++) {
             if (this.tests[i]) {
+                // Stop shifting if j has crossed more fixed-mask separators than i has.
+                // This prevents digits from bleeding across section boundaries (e.g. 99.99.9999).
+                if (this.countFixedChars(begin, i + 1) !== this.countFixedChars(end + 1, j + 1)) {
+                    break;
+                }
+
                 if (j < (this.len as number) && this.tests[i].test(this.buffer[j])) {
                     this.buffer[i] = this.buffer[j];
                     this.buffer[j] = this.getPlaceholder(j);
@@ -1070,6 +1088,18 @@ export class InputMask extends BaseInput<InputMaskPassThrough> {
         return pos;
     }
 
+    /**
+     * Count the number of fixed (non-editable) mask characters in the range [from, to).
+     * Fixed characters are those where tests[k] is null (e.g. separators like '.' or '/').
+     */
+    private countFixedChars(from: number, to: number): number {
+        let count = 0;
+        for (let k = from; k < to; k++) {
+            if (!this.tests[k]) count++;
+        }
+        return count;
+    }
+
     shiftL(begin: number, end: number) {
         let i, j;
 
@@ -1079,6 +1109,12 @@ export class InputMask extends BaseInput<InputMaskPassThrough> {
 
         for (i = begin, j = this.seekNext(end); i < (this.len as number); i++) {
             if (this.tests[i]) {
+                // Stop shifting if j has crossed more fixed-mask separators than i has.
+                // This prevents digits from bleeding across section boundaries (e.g. 99.99.9999).
+                if (this.countFixedChars(begin, i + 1) !== this.countFixedChars(end + 1, j + 1)) {
+                    break;
+                }
+
                 if (j < (this.len as number) && this.tests[i].test(this.buffer[j])) {
                     this.buffer[i] = this.buffer[j];
                     this.buffer[j] = this.getPlaceholder(j);