diff --git a/java/kotlin-extractor/src/main/kotlin/KotlinFileExtractor.kt b/java/kotlin-extractor/src/main/kotlin/KotlinFileExtractor.kt
index adcc725762a..e18613b3048 100644
--- a/java/kotlin-extractor/src/main/kotlin/KotlinFileExtractor.kt
+++ b/java/kotlin-extractor/src/main/kotlin/KotlinFileExtractor.kt
@@ -4986,6 +4986,40 @@ open class KotlinFileExtractor(
             else -> false
         }
 
+    /**
+     * For a property/delegated-property setter [IrCall] desugared from an assignment
+     * `lhs = rhs` (origin [IrStatementOrigin.EQ]), returns the end offset of the assigned
+     * value (the call's last value argument) when it extends past the call's own end offset,
+     * or null otherwise.
+     *
+     * The K1 frontend records such a setter call (and its synthetic implicit-`this` receiver
+     * and synthetic reflection arguments) at the assignment's left-hand side only
+     * (`varResource0 = 3` -> `37:9:37:20`), whereas K2 spans the whole assignment through the
+     * assigned value (`37:9:37:24`). The setter call *is* the desugaring of the whole
+     * assignment, so K2's span is the more intuitive one; we converge K1 onto it. Returns null
+     * under K2 (where the call already spans the assigned value, so no widening is needed) and
+     * for any non-assignment call.
+     */
+    private fun getSetterCallAssignedValueEndOffset(c: IrCall): Int? {
+        if (c.origin != IrStatementOrigin.EQ) return null
+        val n = c.codeQlValueArgumentsCount
+        if (n == 0) return null
+        val assignedValue = c.codeQlGetValueArgument(n - 1) ?: return null
+        val valueEnd = assignedValue.endOffset
+        if (
+            valueEnd == UNDEFINED_OFFSET ||
+                valueEnd == SYNTHETIC_OFFSET ||
+                c.startOffset == UNDEFINED_OFFSET ||
+                c.startOffset == SYNTHETIC_OFFSET ||
+                c.endOffset == UNDEFINED_OFFSET ||
+                c.endOffset == SYNTHETIC_OFFSET
+        ) {
+            return null
+        }
+        if (valueEnd <= c.endOffset) return null
+        return valueEnd
+    }
+
     private fun extractCall(
         c: IrCall,
         callable: Label<out DbCallable>,
@@ -5977,7 +6011,29 @@ open class KotlinFileExtractor(
                     }
                 }
                 else -> {
-                    extractMethodAccess(target, true, true)
+                    // A property/delegated-property setter call desugared from an assignment
+                    // `lhs = rhs` is anchored by K1 at the left-hand side only, while K2 spans the
+                    // whole assignment through the assigned value. Widen the K1 span to match by
+                    // remapping the call's exact offset pair (which its synthetic implicit-`this`
+                    // receiver and synthetic reflection arguments also carry) onto one that runs
+                    // through the assigned value. Real source arguments have their own offsets and
+                    // are unaffected; the remap is a no-op under K2 (helper returns null).
+                    val assignedValueEnd = getSetterCallAssignedValueEndOffset(c)
+                    if (assignedValueEnd != null) {
+                        val previousRemap = tw.scopedOffsetRemap
+                        tw.scopedOffsetRemap =
+                            Pair(
+                                Pair(c.startOffset, c.endOffset),
+                                Pair(c.startOffset, assignedValueEnd)
+                            )
+                        try {
+                            extractMethodAccess(target, true, true)
+                        } finally {
+                            tw.scopedOffsetRemap = previousRemap
+                        }
+                    } else {
+                        extractMethodAccess(target, true, true)
+                    }
                 }
             }
         }
diff --git a/java/ql/test-kotlin1/library-tests/exprs/exprs.expected b/java/ql/test-kotlin1/library-tests/exprs/exprs.expected
index 949b14ff3ec..289bf8936c0 100644
--- a/java/ql/test-kotlin1/library-tests/exprs/exprs.expected
+++ b/java/ql/test-kotlin1/library-tests/exprs/exprs.expected
@@ -90,9 +90,9 @@
 | delegatedProperties.kt:20:17:20:28 | <get-varResource1>(...) | delegatedProperties.kt:18:5:40:5 | fn | MethodCall |
 | delegatedProperties.kt:20:17:20:28 | Object | delegatedProperties.kt:18:5:40:5 | fn | TypeAccess |
 | delegatedProperties.kt:20:17:20:28 | new (...) | delegatedProperties.kt:18:5:40:5 | fn | ClassInstanceExpr |
-| delegatedProperties.kt:21:9:21:20 | <set-varResource1>(...) | delegatedProperties.kt:18:5:40:5 | fn | MethodCall |
-| delegatedProperties.kt:21:9:21:20 | Object | delegatedProperties.kt:18:5:40:5 | fn | TypeAccess |
-| delegatedProperties.kt:21:9:21:20 | new (...) | delegatedProperties.kt:18:5:40:5 | fn | ClassInstanceExpr |
+| delegatedProperties.kt:21:9:21:24 | <set-varResource1>(...) | delegatedProperties.kt:18:5:40:5 | fn | MethodCall |
+| delegatedProperties.kt:21:9:21:24 | Object | delegatedProperties.kt:18:5:40:5 | fn | TypeAccess |
+| delegatedProperties.kt:21:9:21:24 | new (...) | delegatedProperties.kt:18:5:40:5 | fn | ClassInstanceExpr |
 | delegatedProperties.kt:21:24:21:24 | 2 | delegatedProperties.kt:18:5:40:5 | fn | IntegerLiteral |
 | delegatedProperties.kt:23:9:23:31 | String | file://:0:0:0:0 | <none> | TypeAccess |
 | delegatedProperties.kt:23:9:23:31 | name$delegate | delegatedProperties.kt:18:5:40:5 | fn | LocalVariableDeclExpr |
@@ -140,8 +140,8 @@
 | delegatedProperties.kt:28:50:28:71 | ? ... | file://:0:0:0:0 | <none> | WildcardTypeAccess |
 | delegatedProperties.kt:28:50:28:71 | KProperty<?> | file://:0:0:0:0 | <none> | TypeAccess |
 | delegatedProperties.kt:28:74:28:83 | int | file://:0:0:0:0 | <none> | TypeAccess |
-| delegatedProperties.kt:29:17:29:24 | setCurValue(...) | delegatedProperties.kt:28:22:30:13 | setValue | MethodCall |
-| delegatedProperties.kt:29:17:29:24 | this | delegatedProperties.kt:28:22:30:13 | setValue | ThisAccess |
+| delegatedProperties.kt:29:17:29:32 | setCurValue(...) | delegatedProperties.kt:28:22:30:13 | setValue | MethodCall |
+| delegatedProperties.kt:29:17:29:32 | this | delegatedProperties.kt:28:22:30:13 | setValue | ThisAccess |
 | delegatedProperties.kt:29:28:29:32 | value | delegatedProperties.kt:28:22:30:13 | setValue | VarAccess |
 | delegatedProperties.kt:33:9:33:76 | int | file://:0:0:0:0 | <none> | TypeAccess |
 | delegatedProperties.kt:33:9:33:76 | readOnly$delegate | delegatedProperties.kt:18:5:40:5 | fn | LocalVariableDeclExpr |
@@ -198,8 +198,8 @@
 | delegatedProperties.kt:36:9:36:29 | println(...) | delegatedProperties.kt:18:5:40:5 | fn | MethodCall |
 | delegatedProperties.kt:36:17:36:28 | getVarResource0(...) | delegatedProperties.kt:18:5:40:5 | fn | MethodCall |
 | delegatedProperties.kt:36:17:36:28 | this | delegatedProperties.kt:18:5:40:5 | fn | ThisAccess |
-| delegatedProperties.kt:37:9:37:20 | setVarResource0(...) | delegatedProperties.kt:18:5:40:5 | fn | MethodCall |
-| delegatedProperties.kt:37:9:37:20 | this | delegatedProperties.kt:18:5:40:5 | fn | ThisAccess |
+| delegatedProperties.kt:37:9:37:24 | setVarResource0(...) | delegatedProperties.kt:18:5:40:5 | fn | MethodCall |
+| delegatedProperties.kt:37:9:37:24 | this | delegatedProperties.kt:18:5:40:5 | fn | ThisAccess |
 | delegatedProperties.kt:37:24:37:24 | 3 | delegatedProperties.kt:18:5:40:5 | fn | IntegerLiteral |
 | delegatedProperties.kt:39:9:39:51 | int | file://:0:0:0:0 | <none> | TypeAccess |
 | delegatedProperties.kt:39:9:39:51 | varResource2$delegate | delegatedProperties.kt:18:5:40:5 | fn | LocalVariableDeclExpr |
diff --git a/java/ql/test-kotlin1/library-tests/generic-instance-methods/test.expected b/java/ql/test-kotlin1/library-tests/generic-instance-methods/test.expected
index c3180eb4162..7e9dc790b47 100644
--- a/java/ql/test-kotlin1/library-tests/generic-instance-methods/test.expected
+++ b/java/ql/test-kotlin1/library-tests/generic-instance-methods/test.expected
@@ -7,7 +7,7 @@ calls
 | Test.java:27:5:27:24 | getter(...) | Test.java:16:22:16:25 | user | Test.java:14:14:14:17 | Test | Generic2.class:0:0:0:0 | getter | Generic2.class:0:0:0:0 | Generic2<? super String> |
 | test.kt:5:32:5:46 | identity(...) | test.kt:5:3:5:46 | identity2 | test.kt:1:1:13:1 | Generic | test.kt:6:3:6:35 | identity | test.kt:1:1:13:1 | Generic |
 | test.kt:7:21:7:26 | getStored(...) | test.kt:7:3:7:26 | getter | test.kt:1:1:13:1 | Generic | test.kt:3:3:3:12 | getStored | test.kt:1:1:13:1 | Generic |
-| test.kt:8:26:8:31 | setStored(...) | test.kt:8:3:8:41 | setter | test.kt:1:1:13:1 | Generic | test.kt:3:3:3:12 | setStored | test.kt:1:1:13:1 | Generic |
+| test.kt:8:26:8:39 | setStored(...) | test.kt:8:3:8:41 | setter | test.kt:1:1:13:1 | Generic | test.kt:3:3:3:12 | setStored | test.kt:1:1:13:1 | Generic |
 | test.kt:11:44:11:70 | privateid(...) | test.kt:11:3:11:70 | callPrivateId | test.kt:1:1:13:1 | Generic | file:///!unknown-binary-location/Generic.class:0:0:0:0 | privateid | file:///!unknown-binary-location/Generic.class:0:0:0:0 | Generic<String> |
 | test.kt:18:3:18:35 | identity(...) | test.kt:15:1:28:1 | user | test.kt:0:0:0:0 | TestKt | file:///!unknown-binary-location/Generic.class:0:0:0:0 | identity | file:///!unknown-binary-location/Generic.class:0:0:0:0 | Generic<String> |
 | test.kt:19:3:19:36 | identity2(...) | test.kt:15:1:28:1 | user | test.kt:0:0:0:0 | TestKt | file:///!unknown-binary-location/Generic.class:0:0:0:0 | identity2 | file:///!unknown-binary-location/Generic.class:0:0:0:0 | Generic<String> |
diff --git a/java/ql/test-kotlin1/library-tests/jvmstatic-annotation/test.expected b/java/ql/test-kotlin1/library-tests/jvmstatic-annotation/test.expected
index 1071f7a6e03..58a94794d17 100644
--- a/java/ql/test-kotlin1/library-tests/jvmstatic-annotation/test.expected
+++ b/java/ql/test-kotlin1/library-tests/jvmstatic-annotation/test.expected
@@ -32,19 +32,19 @@ staticMembers
 | test.kt:11:3:27:3 | Companion | test.kt:16:16:16:43 | setStaticProp(...) | test.kt:16:16:16:43 | HasCompanion.Companion | instance |
 | test.kt:11:3:27:3 | Companion | test.kt:20:18:20:45 | getPropWithStaticGetter(...) | test.kt:20:18:20:45 | HasCompanion.Companion | instance |
 | test.kt:11:3:27:3 | Companion | test.kt:20:26:20:45 | getPropWithStaticSetter(...) | test.kt:20:26:20:45 | this | instance |
-| test.kt:11:3:27:3 | Companion | test.kt:21:24:21:43 | setPropWithStaticSetter(...) | test.kt:21:24:21:43 | this | instance |
+| test.kt:11:3:27:3 | Companion | test.kt:21:24:21:47 | setPropWithStaticSetter(...) | test.kt:21:24:21:47 | this | instance |
 | test.kt:11:3:27:3 | Companion | test.kt:24:15:24:34 | getPropWithStaticGetter(...) | test.kt:24:15:24:34 | this | instance |
 | test.kt:11:3:27:3 | Companion | test.kt:25:18:25:60 | setPropWithStaticSetter(...) | test.kt:25:18:25:60 | HasCompanion.Companion | instance |
-| test.kt:11:3:27:3 | Companion | test.kt:25:35:25:54 | setPropWithStaticGetter(...) | test.kt:25:35:25:54 | this | instance |
+| test.kt:11:3:27:3 | Companion | test.kt:25:35:25:58 | setPropWithStaticGetter(...) | test.kt:25:35:25:58 | this | instance |
 | test.kt:11:3:27:3 | Companion | test.kt:52:3:52:32 | staticMethod(...) | test.kt:52:3:52:14 | Companion | instance |
 | test.kt:11:3:27:3 | Companion | test.kt:53:3:53:35 | nonStaticMethod(...) | test.kt:53:3:53:14 | Companion | instance |
-| test.kt:11:3:27:3 | Companion | test.kt:54:3:54:25 | setStaticProp(...) | test.kt:54:3:54:14 | Companion | instance |
+| test.kt:11:3:27:3 | Companion | test.kt:54:3:54:54 | setStaticProp(...) | test.kt:54:3:54:14 | Companion | instance |
 | test.kt:11:3:27:3 | Companion | test.kt:54:29:54:54 | getNonStaticProp(...) | test.kt:54:29:54:40 | Companion | instance |
-| test.kt:11:3:27:3 | Companion | test.kt:55:3:55:28 | setNonStaticProp(...) | test.kt:55:3:55:14 | Companion | instance |
+| test.kt:11:3:27:3 | Companion | test.kt:55:3:55:54 | setNonStaticProp(...) | test.kt:55:3:55:14 | Companion | instance |
 | test.kt:11:3:27:3 | Companion | test.kt:55:32:55:54 | getStaticProp(...) | test.kt:55:32:55:43 | Companion | instance |
-| test.kt:11:3:27:3 | Companion | test.kt:56:3:56:35 | setPropWithStaticGetter(...) | test.kt:56:3:56:14 | Companion | instance |
+| test.kt:11:3:27:3 | Companion | test.kt:56:3:56:71 | setPropWithStaticGetter(...) | test.kt:56:3:56:14 | Companion | instance |
 | test.kt:11:3:27:3 | Companion | test.kt:56:39:56:71 | getPropWithStaticSetter(...) | test.kt:56:39:56:50 | Companion | instance |
-| test.kt:11:3:27:3 | Companion | test.kt:57:3:57:35 | setPropWithStaticSetter(...) | test.kt:57:3:57:14 | Companion | instance |
+| test.kt:11:3:27:3 | Companion | test.kt:57:3:57:71 | setPropWithStaticSetter(...) | test.kt:57:3:57:14 | Companion | instance |
 | test.kt:11:3:27:3 | Companion | test.kt:57:39:57:71 | getPropWithStaticGetter(...) | test.kt:57:39:57:50 | Companion | instance |
 | test.kt:31:1:47:1 | NonCompanion | JavaUser.java:13:5:13:34 | staticMethod(...) | JavaUser.java:13:5:13:16 | NonCompanion | static |
 | test.kt:31:1:47:1 | NonCompanion | JavaUser.java:14:5:14:46 | nonStaticMethod(...) | JavaUser.java:14:5:14:25 | NonCompanion.INSTANCE | instance |
@@ -59,16 +59,16 @@ staticMembers
 | test.kt:31:1:47:1 | NonCompanion | test.kt:33:52:33:69 | nonStaticMethod(...) | test.kt:33:52:33:69 | NonCompanion.INSTANCE | instance |
 | test.kt:31:1:47:1 | NonCompanion | test.kt:34:44:34:58 | staticMethod(...) | test.kt:34:44:34:58 | NonCompanion | static |
 | test.kt:31:1:47:1 | NonCompanion | test.kt:40:24:40:43 | getPropWithStaticSetter(...) | test.kt:40:24:40:43 | NonCompanion.INSTANCE | instance |
-| test.kt:31:1:47:1 | NonCompanion | test.kt:41:22:41:41 | setPropWithStaticSetter(...) | test.kt:41:22:41:41 | NonCompanion | static |
+| test.kt:31:1:47:1 | NonCompanion | test.kt:41:22:41:45 | setPropWithStaticSetter(...) | test.kt:41:22:41:45 | NonCompanion | static |
 | test.kt:31:1:47:1 | NonCompanion | test.kt:44:13:44:32 | getPropWithStaticGetter(...) | test.kt:44:13:44:32 | NonCompanion | static |
-| test.kt:31:1:47:1 | NonCompanion | test.kt:45:33:45:52 | setPropWithStaticGetter(...) | test.kt:45:33:45:52 | NonCompanion.INSTANCE | instance |
+| test.kt:31:1:47:1 | NonCompanion | test.kt:45:33:45:56 | setPropWithStaticGetter(...) | test.kt:45:33:45:56 | NonCompanion.INSTANCE | instance |
 | test.kt:31:1:47:1 | NonCompanion | test.kt:60:3:60:32 | staticMethod(...) | test.kt:60:3:60:32 | NonCompanion | static |
 | test.kt:31:1:47:1 | NonCompanion | test.kt:61:3:61:35 | nonStaticMethod(...) | test.kt:61:3:61:14 | INSTANCE | instance |
-| test.kt:31:1:47:1 | NonCompanion | test.kt:62:3:62:25 | setStaticProp(...) | test.kt:62:3:62:25 | NonCompanion | static |
+| test.kt:31:1:47:1 | NonCompanion | test.kt:62:3:62:54 | setStaticProp(...) | test.kt:62:3:62:54 | NonCompanion | static |
 | test.kt:31:1:47:1 | NonCompanion | test.kt:62:29:62:54 | getNonStaticProp(...) | test.kt:62:29:62:40 | INSTANCE | instance |
-| test.kt:31:1:47:1 | NonCompanion | test.kt:63:3:63:28 | setNonStaticProp(...) | test.kt:63:3:63:14 | INSTANCE | instance |
+| test.kt:31:1:47:1 | NonCompanion | test.kt:63:3:63:54 | setNonStaticProp(...) | test.kt:63:3:63:14 | INSTANCE | instance |
 | test.kt:31:1:47:1 | NonCompanion | test.kt:63:32:63:54 | getStaticProp(...) | test.kt:63:32:63:54 | NonCompanion | static |
-| test.kt:31:1:47:1 | NonCompanion | test.kt:64:3:64:35 | setPropWithStaticGetter(...) | test.kt:64:3:64:14 | INSTANCE | instance |
+| test.kt:31:1:47:1 | NonCompanion | test.kt:64:3:64:71 | setPropWithStaticGetter(...) | test.kt:64:3:64:14 | INSTANCE | instance |
 | test.kt:31:1:47:1 | NonCompanion | test.kt:64:39:64:71 | getPropWithStaticSetter(...) | test.kt:64:39:64:50 | INSTANCE | instance |
-| test.kt:31:1:47:1 | NonCompanion | test.kt:65:3:65:35 | setPropWithStaticSetter(...) | test.kt:65:3:65:35 | NonCompanion | static |
+| test.kt:31:1:47:1 | NonCompanion | test.kt:65:3:65:71 | setPropWithStaticSetter(...) | test.kt:65:3:65:71 | NonCompanion | static |
 | test.kt:31:1:47:1 | NonCompanion | test.kt:65:39:65:71 | getPropWithStaticGetter(...) | test.kt:65:39:65:71 | NonCompanion | static |