diff --git a/src/dotty/tools/dotc/core/Flags.scala b/src/dotty/tools/dotc/core/Flags.scala
index bdd6bbdcf192..0cdae6b98c17 100644
--- a/src/dotty/tools/dotc/core/Flags.scala
+++ b/src/dotty/tools/dotc/core/Flags.scala
@@ -448,7 +448,7 @@ object Flags {
   /** Flags guaranteed to be set upon symbol creation */
   final val FromStartFlags =
     AccessFlags | Module | Package | Deferred | Final | MethodOrHKCommon | Param | ParamAccessor | Scala2ExistentialCommon |
-    InSuperCall | Touched | JavaStatic | CovariantOrOuter | ContravariantOrLabel | ExpandedName | AccessorOrSealed |
+    Mutable.toCommonFlags | InSuperCall | Touched | JavaStatic | CovariantOrOuter | ContravariantOrLabel | ExpandedName | AccessorOrSealed |
     CaseAccessorOrBaseTypeArg | Fresh | Frozen | Erroneous | ImplicitCommon | Permanent | Synthetic |
     LazyOrTrait | SuperAccessorOrScala2x | SelfNameOrImplClass
 
diff --git a/src/dotty/tools/dotc/typer/Namer.scala b/src/dotty/tools/dotc/typer/Namer.scala
index d1074364c702..11f16774688d 100644
--- a/src/dotty/tools/dotc/typer/Namer.scala
+++ b/src/dotty/tools/dotc/typer/Namer.scala
@@ -830,8 +830,8 @@ class Namer { typer: Typer =>
 
       // println(s"final inherited for $sym: ${inherited.toString}") !!!
       // println(s"owner = ${sym.owner}, decls = ${sym.owner.info.decls.show}")
-      def isInline = sym.is(Final, butNot = Method)
-
+      def isInline = sym.is(Final, butNot = Method | Mutable)
+      
       // Widen rhs type and approximate `|' but keep ConstantTypes if
       // definition is inline (i.e. final in Scala2).
       def widenRhs(tp: Type): Type = tp.widenTermRefExpr match {
diff --git a/tests/pos/i1285.scala b/tests/pos/i1285.scala
new file mode 100644
index 000000000000..3fb267653b4c
--- /dev/null
+++ b/tests/pos/i1285.scala
@@ -0,0 +1,4 @@
+class Test {
+  final var x = false
+  x = true
+}