diff --git a/src/Compiler/Checking/CheckDeclarations.fs b/src/Compiler/Checking/CheckDeclarations.fs
index 11a372bb5c5..36f49053ad8 100644
--- a/src/Compiler/Checking/CheckDeclarations.fs
+++ b/src/Compiler/Checking/CheckDeclarations.fs
@@ -4035,7 +4035,7 @@ module TcDeclarations =
                         let mLetPortion = synExpr.Range
                         let fldId = ident (CompilerGeneratedName id.idText, mLetPortion)
                         let headPat = SynPat.LongIdent (SynLongIdent([fldId], [], [None]), None, Some noInferredTypars, SynArgPats.Pats [], None, mLetPortion)
-                        let retInfo = match tyOpt with None -> None | Some ty -> Some (SynReturnInfo((ty, SynInfo.unnamedRetVal), ty.Range))
+                        let retInfo = match tyOpt with None -> None | Some ty -> Some (None, SynReturnInfo((ty, SynInfo.unnamedRetVal), ty.Range))
                         let isMutable = 
                             match propKind with 
                             | SynMemberKind.PropertySet 
@@ -4077,7 +4077,7 @@ module TcDeclarations =
                             | SynMemberKind.PropertyGetSet -> 
                                 let getter = 
                                     let rhsExpr = SynExpr.Ident fldId
-                                    let retInfo = match tyOpt with None -> None | Some ty -> Some (SynReturnInfo((ty, SynInfo.unnamedRetVal), ty.Range))
+                                    let retInfo = match tyOpt with None -> None | Some ty -> Some (None, SynReturnInfo((ty, SynInfo.unnamedRetVal), ty.Range))
                                     let attribs = mkAttributeList attribs mMemberPortion
                                     let binding = mkSynBinding (xmlDoc, headPat) (access, false, false, mMemberPortion, DebugPointAtBinding.NoneAtInvisible, retInfo, rhsExpr, rhsExpr.Range, [], attribs, Some memberFlags, SynBindingTrivia.Zero)
                                     SynMemberDefn.Member (binding, mMemberPortion) 
diff --git a/src/Compiler/Checking/CheckExpressions.fs b/src/Compiler/Checking/CheckExpressions.fs
index 9e6524f2627..65515a38a69 100644
--- a/src/Compiler/Checking/CheckExpressions.fs
+++ b/src/Compiler/Checking/CheckExpressions.fs
@@ -10246,7 +10246,7 @@ and TcNormalizedBinding declKind (cenv: cenv) env tpenv overallTy safeThisValOpt
                      |> fun (r, v) -> (List.map fst r, List.map snd r, List.map snd v)
             let retAttribs =
                 match rtyOpt with
-                | Some (SynBindingReturnInfo(_, _, Attributes retAttrs)) ->
+                | Some (SynBindingReturnInfo(attributes = Attributes retAttrs)) ->
                     rotRetAttribs @ TcAttrs AttributeTargets.ReturnValue true retAttrs
                 | None -> rotRetAttribs
             let valSynData =
@@ -10894,7 +10894,7 @@ and ApplyTypesFromArgumentPatterns (cenv: cenv, env, optionalArgsOK, ty, m, tpen
     | [] ->
         match retInfoOpt with
         | None -> ()
-        | Some (SynBindingReturnInfo (retInfoTy, m, _)) ->
+        | Some (SynBindingReturnInfo (typeName = retInfoTy; range = m)) ->
             let retInfoTy, _ = TcTypeAndRecover cenv NewTyparsOK CheckCxs ItemOccurence.UseInType WarnOnIWSAM.Yes env tpenv retInfoTy
             UnifyTypes cenv env m ty retInfoTy
         // Property setters always have "unit" return type
diff --git a/src/Compiler/Service/ServiceParsedInputOps.fs b/src/Compiler/Service/ServiceParsedInputOps.fs
index 7317df67378..b98bd2248c9 100644
--- a/src/Compiler/Service/ServiceParsedInputOps.fs
+++ b/src/Compiler/Service/ServiceParsedInputOps.fs
@@ -647,7 +647,7 @@ module ParsedInput =
             |> Option.orElseWith (fun () -> walkExpr e)
             |> Option.orElseWith (fun () ->
                 match returnInfo with
-                | Some (SynBindingReturnInfo (t, _, _)) -> walkType t
+                | Some (SynBindingReturnInfo (typeName = t)) -> walkType t
                 | None -> None)
 
         and walkInterfaceImpl (SynInterfaceImpl (bindings = bindings)) = List.tryPick walkBinding bindings
@@ -1662,7 +1662,9 @@ module ParsedInput =
             List.iter walkAttribute attrs
             walkPat pat
             walkExpr e
-            returnInfo |> Option.iter (fun (SynBindingReturnInfo (t, _, _)) -> walkType t)
+
+            returnInfo
+            |> Option.iter (fun (SynBindingReturnInfo (typeName = t)) -> walkType t)
 
         and walkInterfaceImpl (SynInterfaceImpl (bindings = bindings)) = List.iter walkBinding bindings
 
diff --git a/src/Compiler/SyntaxTree/ParseHelpers.fs b/src/Compiler/SyntaxTree/ParseHelpers.fs
index b97bfe2f7c8..fee75795e33 100644
--- a/src/Compiler/SyntaxTree/ParseHelpers.fs
+++ b/src/Compiler/SyntaxTree/ParseHelpers.fs
@@ -422,11 +422,11 @@ let mkSynMemberDefnGetSet
     (parseState: IParseState)
     (opt_inline: bool)
     (mWith: range)
-    (classDefnMemberGetSetElements: (bool * SynAttributeList list * (SynPat * range) * SynReturnInfo option * range option * SynExpr * range) list)
+    (classDefnMemberGetSetElements: (bool * SynAttributeList list * (SynPat * range) * (range option * SynReturnInfo) option * range option * SynExpr * range) list)
     (mAnd: range option)
     (mWhole: range)
     (propertyNameBindingPat: SynPat)
-    (optPropertyType: SynReturnInfo option)
+    (optPropertyType: (range option * SynReturnInfo) option)
     (visNoLongerUsed: SynAccess option)
     flagsBuilderAndLeadingKeyword
     (attrs: SynAttributeList list)
diff --git a/src/Compiler/SyntaxTree/ParseHelpers.fsi b/src/Compiler/SyntaxTree/ParseHelpers.fsi
index 1192608dbfb..353d8c973c6 100644
--- a/src/Compiler/SyntaxTree/ParseHelpers.fsi
+++ b/src/Compiler/SyntaxTree/ParseHelpers.fsi
@@ -166,11 +166,11 @@ val mkSynMemberDefnGetSet:
     parseState: IParseState ->
     opt_inline: bool ->
     mWith: range ->
-    classDefnMemberGetSetElements: (bool * SynAttributeList list * (SynPat * range) * SynReturnInfo option * range option * SynExpr * range) list ->
+    classDefnMemberGetSetElements: (bool * SynAttributeList list * (SynPat * range) * (range option * SynReturnInfo) option * range option * SynExpr * range) list ->
     mAnd: range option ->
     mWhole: range ->
     propertyNameBindingPat: SynPat ->
-    optPropertyType: SynReturnInfo option ->
+    optPropertyType: (range option * SynReturnInfo) option ->
     visNoLongerUsed: SynAccess option ->
     flagsBuilderAndLeadingKeyword: (SynMemberKind -> SynMemberFlags) * SynLeadingKeyword ->
         attrs: SynAttributeList list ->
diff --git a/src/Compiler/SyntaxTree/SyntaxTree.fs b/src/Compiler/SyntaxTree/SyntaxTree.fs
index bdbf10665d0..540adc029e1 100644
--- a/src/Compiler/SyntaxTree/SyntaxTree.fs
+++ b/src/Compiler/SyntaxTree/SyntaxTree.fs
@@ -1065,7 +1065,8 @@ type SynBinding =
     member x.RangeOfHeadPattern = let (SynBinding (headPat = headPat)) = x in headPat.Range
 
 [<NoEquality; NoComparison>]
-type SynBindingReturnInfo = SynBindingReturnInfo of typeName: SynType * range: range * attributes: SynAttributes
+type SynBindingReturnInfo =
+    | SynBindingReturnInfo of typeName: SynType * range: range * attributes: SynAttributes * trivia: SynBindingReturnInfoTrivia
 
 [<NoComparison; RequireQualifiedAccess; CustomEquality>]
 type SynMemberFlags =
diff --git a/src/Compiler/SyntaxTree/SyntaxTree.fsi b/src/Compiler/SyntaxTree/SyntaxTree.fsi
index eeee35985e0..3e05507b340 100644
--- a/src/Compiler/SyntaxTree/SyntaxTree.fsi
+++ b/src/Compiler/SyntaxTree/SyntaxTree.fsi
@@ -1209,7 +1209,12 @@ type SynBinding =
 
 /// Represents the return information in a binding for a 'let' or 'member' declaration
 [<NoEquality; NoComparison>]
-type SynBindingReturnInfo = SynBindingReturnInfo of typeName: SynType * range: range * attributes: SynAttributes
+type SynBindingReturnInfo =
+    | SynBindingReturnInfo of
+        typeName: SynType *
+        range: range *
+        attributes: SynAttributes *
+        trivia: SynBindingReturnInfoTrivia
 
 /// Represents the flags for a 'member' declaration
 [<NoComparison; RequireQualifiedAccess; CustomEquality>]
diff --git a/src/Compiler/SyntaxTree/SyntaxTreeOps.fs b/src/Compiler/SyntaxTree/SyntaxTreeOps.fs
index 56eb08fee4f..72cfa230342 100644
--- a/src/Compiler/SyntaxTree/SyntaxTreeOps.fs
+++ b/src/Compiler/SyntaxTree/SyntaxTreeOps.fs
@@ -673,8 +673,8 @@ let mkSynBindingRhs staticOptimizations rhsExpr mRhs retInfo =
 
     let rhsExpr, retTyOpt =
         match retInfo with
-        | Some (SynReturnInfo ((ty, SynArgInfo (rAttribs, _, _)), tym)) ->
-            SynExpr.Typed(rhsExpr, ty, rhsExpr.Range), Some(SynBindingReturnInfo(ty, tym, rAttribs))
+        | Some (mColon, SynReturnInfo ((ty, SynArgInfo (rAttribs, _, _)), tym)) ->
+            SynExpr.Typed(rhsExpr, ty, rhsExpr.Range), Some(SynBindingReturnInfo(ty, tym, rAttribs, { ColonRange = mColon }))
         | None -> rhsExpr, None
 
     rhsExpr, retTyOpt
@@ -684,7 +684,7 @@ let mkSynBinding
     (vis, isInline, isMutable, mBind, spBind, retInfo, origRhsExpr, mRhs, staticOptimizations, attrs, memberFlagsOpt, trivia)
     =
     let info =
-        SynInfo.InferSynValData(memberFlagsOpt, Some headPat, retInfo, origRhsExpr)
+        SynInfo.InferSynValData(memberFlagsOpt, Some headPat, Option.map snd retInfo, origRhsExpr)
 
     let rhsExpr, retTyOpt = mkSynBindingRhs staticOptimizations origRhsExpr mRhs retInfo
     let mBind = unionRangeWithXmlDoc xmlDoc mBind
diff --git a/src/Compiler/SyntaxTree/SyntaxTreeOps.fsi b/src/Compiler/SyntaxTree/SyntaxTreeOps.fsi
index 5c9df2c48d7..0d8284d7073 100644
--- a/src/Compiler/SyntaxTree/SyntaxTreeOps.fsi
+++ b/src/Compiler/SyntaxTree/SyntaxTreeOps.fsi
@@ -269,7 +269,7 @@ val mkSynBindingRhs:
     staticOptimizations: (SynStaticOptimizationConstraint list * SynExpr) list ->
     rhsExpr: SynExpr ->
     mRhs: range ->
-    retInfo: SynReturnInfo option ->
+    retInfo: (range option * SynReturnInfo) option ->
         SynExpr * SynBindingReturnInfo option
 
 val mkSynBinding:
@@ -279,7 +279,7 @@ val mkSynBinding:
         isMutable: bool *
         mBind: range *
         spBind: DebugPointAtBinding *
-        retInfo: SynReturnInfo option *
+        retInfo: (range option * SynReturnInfo) option *
         origRhsExpr: SynExpr *
         mRhs: range *
         staticOptimizations: (SynStaticOptimizationConstraint list * SynExpr) list *
diff --git a/src/Compiler/SyntaxTree/SyntaxTrivia.fs b/src/Compiler/SyntaxTree/SyntaxTrivia.fs
index 5fe77d929a1..8f270d2fd80 100644
--- a/src/Compiler/SyntaxTree/SyntaxTrivia.fs
+++ b/src/Compiler/SyntaxTree/SyntaxTrivia.fs
@@ -320,4 +320,8 @@ type SynFieldTrivia =
 
     static member Zero: SynFieldTrivia = { LeadingKeyword = None }
 
+[<NoEquality; NoComparison>]
 type SynTypeOrTrivia = { OrKeyword: range }
+
+[<NoEquality; NoComparison>]
+type SynBindingReturnInfoTrivia = { ColonRange: range option }
diff --git a/src/Compiler/SyntaxTree/SyntaxTrivia.fsi b/src/Compiler/SyntaxTree/SyntaxTrivia.fsi
index cae5db553e6..b3275f4b365 100644
--- a/src/Compiler/SyntaxTree/SyntaxTrivia.fsi
+++ b/src/Compiler/SyntaxTree/SyntaxTrivia.fsi
@@ -428,3 +428,11 @@ type SynTypeOrTrivia =
         /// The syntax range of the `or` keyword
         OrKeyword: range
     }
+
+/// Represents additional information for SynBindingReturnInfo
+[<NoEquality; NoComparison>]
+type SynBindingReturnInfoTrivia =
+    {
+        /// The syntax range of the `:` token
+        ColonRange: range option
+    }
diff --git a/src/Compiler/pars.fsy b/src/Compiler/pars.fsy
index 3114c476616..392192dd2b3 100644
--- a/src/Compiler/pars.fsy
+++ b/src/Compiler/pars.fsy
@@ -2647,7 +2647,7 @@ cPrototype:
             let binding =
                 mkSynBinding 
                     (xmlDoc, bindingPat) 
-                    (vis, false, false, mWholeBindLhs, DebugPointAtBinding.NoneAtInvisible, Some rty, rhsExpr, mRhs, [], attrs, None, trivia)
+                    (vis, false, false, mWholeBindLhs, DebugPointAtBinding.NoneAtInvisible, Some (None, rty), rhsExpr, mRhs, [], attrs, None, trivia)
             [], [binding]) }
 
 /* A list of arguments in an 'extern' DllImport function definition */
@@ -4995,9 +4995,10 @@ opt_topReturnTypeWithTypeConstraints:
      { None } 
 
   | COLON topTypeWithTypeConstraints 
-     { let ty, arity = $2 
+     { let mColon = rhs parseState 1
+       let ty, arity = $2 
        let arity = (match arity with SynValInfo([], rmdata)-> rmdata | _ -> SynInfo.unnamedRetVal)
-       Some (SynReturnInfo((ty, arity), rhs parseState 2)) }
+       Some (Some mColon, SynReturnInfo((ty, arity), rhs parseState 2)) }
 
 topType: 
   | topTupleType RARROW topType 
diff --git a/tests/FSharp.Compiler.Service.Tests/FSharp.CompilerService.SurfaceArea.netstandard.expected b/tests/FSharp.Compiler.Service.Tests/FSharp.CompilerService.SurfaceArea.netstandard.expected
index 66c52c10aed..f4ea65a8572 100644
--- a/tests/FSharp.Compiler.Service.Tests/FSharp.CompilerService.SurfaceArea.netstandard.expected
+++ b/tests/FSharp.Compiler.Service.Tests/FSharp.CompilerService.SurfaceArea.netstandard.expected
@@ -5925,9 +5925,11 @@ FSharp.Compiler.Syntax.SynBindingKind: Int32 Tag
 FSharp.Compiler.Syntax.SynBindingKind: Int32 get_Tag()
 FSharp.Compiler.Syntax.SynBindingKind: System.String ToString()
 FSharp.Compiler.Syntax.SynBindingReturnInfo
-FSharp.Compiler.Syntax.SynBindingReturnInfo: FSharp.Compiler.Syntax.SynBindingReturnInfo NewSynBindingReturnInfo(FSharp.Compiler.Syntax.SynType, FSharp.Compiler.Text.Range, Microsoft.FSharp.Collections.FSharpList`1[FSharp.Compiler.Syntax.SynAttributeList])
+FSharp.Compiler.Syntax.SynBindingReturnInfo: FSharp.Compiler.Syntax.SynBindingReturnInfo NewSynBindingReturnInfo(FSharp.Compiler.Syntax.SynType, FSharp.Compiler.Text.Range, Microsoft.FSharp.Collections.FSharpList`1[FSharp.Compiler.Syntax.SynAttributeList], FSharp.Compiler.SyntaxTrivia.SynBindingReturnInfoTrivia)
 FSharp.Compiler.Syntax.SynBindingReturnInfo: FSharp.Compiler.Syntax.SynType get_typeName()
 FSharp.Compiler.Syntax.SynBindingReturnInfo: FSharp.Compiler.Syntax.SynType typeName
+FSharp.Compiler.Syntax.SynBindingReturnInfo: FSharp.Compiler.SyntaxTrivia.SynBindingReturnInfoTrivia get_trivia()
+FSharp.Compiler.Syntax.SynBindingReturnInfo: FSharp.Compiler.SyntaxTrivia.SynBindingReturnInfoTrivia trivia
 FSharp.Compiler.Syntax.SynBindingReturnInfo: FSharp.Compiler.Text.Range get_range()
 FSharp.Compiler.Syntax.SynBindingReturnInfo: FSharp.Compiler.Text.Range range
 FSharp.Compiler.Syntax.SynBindingReturnInfo: Int32 Tag
@@ -9410,6 +9412,11 @@ FSharp.Compiler.SyntaxTrivia.SynArgPatsNamePatPairsTrivia: FSharp.Compiler.Text.
 FSharp.Compiler.SyntaxTrivia.SynArgPatsNamePatPairsTrivia: FSharp.Compiler.Text.Range get_ParenRange()
 FSharp.Compiler.SyntaxTrivia.SynArgPatsNamePatPairsTrivia: System.String ToString()
 FSharp.Compiler.SyntaxTrivia.SynArgPatsNamePatPairsTrivia: Void .ctor(FSharp.Compiler.Text.Range)
+FSharp.Compiler.SyntaxTrivia.SynBindingReturnInfoTrivia
+FSharp.Compiler.SyntaxTrivia.SynBindingReturnInfoTrivia: Microsoft.FSharp.Core.FSharpOption`1[FSharp.Compiler.Text.Range] ColonRange
+FSharp.Compiler.SyntaxTrivia.SynBindingReturnInfoTrivia: Microsoft.FSharp.Core.FSharpOption`1[FSharp.Compiler.Text.Range] get_ColonRange()
+FSharp.Compiler.SyntaxTrivia.SynBindingReturnInfoTrivia: System.String ToString()
+FSharp.Compiler.SyntaxTrivia.SynBindingReturnInfoTrivia: Void .ctor(Microsoft.FSharp.Core.FSharpOption`1[FSharp.Compiler.Text.Range])
 FSharp.Compiler.SyntaxTrivia.SynBindingTrivia
 FSharp.Compiler.SyntaxTrivia.SynBindingTrivia: FSharp.Compiler.SyntaxTrivia.SynBindingTrivia Zero
 FSharp.Compiler.SyntaxTrivia.SynBindingTrivia: FSharp.Compiler.SyntaxTrivia.SynBindingTrivia get_Zero()
@@ -9826,13 +9833,8 @@ FSharp.Compiler.SyntaxTrivia.SynTypeFunTrivia: FSharp.Compiler.Text.Range get_Ar
 FSharp.Compiler.SyntaxTrivia.SynTypeFunTrivia: System.String ToString()
 FSharp.Compiler.SyntaxTrivia.SynTypeFunTrivia: Void .ctor(FSharp.Compiler.Text.Range)
 FSharp.Compiler.SyntaxTrivia.SynTypeOrTrivia
-FSharp.Compiler.SyntaxTrivia.SynTypeOrTrivia: Boolean Equals(FSharp.Compiler.SyntaxTrivia.SynTypeOrTrivia)
-FSharp.Compiler.SyntaxTrivia.SynTypeOrTrivia: Boolean Equals(System.Object)
-FSharp.Compiler.SyntaxTrivia.SynTypeOrTrivia: Boolean Equals(System.Object, System.Collections.IEqualityComparer)
 FSharp.Compiler.SyntaxTrivia.SynTypeOrTrivia: FSharp.Compiler.Text.Range OrKeyword
 FSharp.Compiler.SyntaxTrivia.SynTypeOrTrivia: FSharp.Compiler.Text.Range get_OrKeyword()
-FSharp.Compiler.SyntaxTrivia.SynTypeOrTrivia: Int32 GetHashCode()
-FSharp.Compiler.SyntaxTrivia.SynTypeOrTrivia: Int32 GetHashCode(System.Collections.IEqualityComparer)
 FSharp.Compiler.SyntaxTrivia.SynTypeOrTrivia: System.String ToString()
 FSharp.Compiler.SyntaxTrivia.SynTypeOrTrivia: Void .ctor(FSharp.Compiler.Text.Range)
 FSharp.Compiler.SyntaxTrivia.SynUnionCaseTrivia
diff --git a/tests/service/SyntaxTreeTests/BindingTests.fs b/tests/service/SyntaxTreeTests/BindingTests.fs
index 5a05af975e2..e2afdfd7f93 100644
--- a/tests/service/SyntaxTreeTests/BindingTests.fs
+++ b/tests/service/SyntaxTreeTests/BindingTests.fs
@@ -399,3 +399,43 @@ let b : int * string * bool = 1, "", false
     ]) ])) ->
         Assert.Pass ()
     | _ -> Assert.Fail $"Could not get valid AST, got {parseResults}"
+
+[<Test>]
+let ``Colon before return type is part of trivia`` () =
+    let parseResults = 
+        getParseResults """
+let x y : int = failwith "todo"
+"""
+
+    match parseResults with
+    | ParsedInput.ImplFile (ParsedImplFileInput (contents = [ SynModuleOrNamespace.SynModuleOrNamespace(decls = [
+        SynModuleDecl.Let(bindings = [
+            SynBinding(returnInfo =
+                Some (SynBindingReturnInfo(trivia = { ColonRange = Some mColon })))
+        ])
+    ]) ])) ->
+        assertRange (2,8) (2,9) mColon
+    | _ -> Assert.Fail $"Could not get valid AST, got {parseResults}"
+
+[<Test>]
+let ``Colon before return type is part of trivia in properties`` () =
+    let parseResults = 
+        getParseResults """
+type X =
+    member this.Y with get():int = 1 and set (_:int):unit = ()
+"""
+
+    match parseResults with
+    | ParsedInput.ImplFile (ParsedImplFileInput (contents = [ SynModuleOrNamespace.SynModuleOrNamespace(decls = [
+        SynModuleDecl.Types(typeDefns = [
+            SynTypeDefn(typeRepr = SynTypeDefnRepr.ObjectModel(members = [
+                SynMemberDefn.GetSetMember(
+                    memberDefnForGet = Some(SynBinding(returnInfo = Some (SynBindingReturnInfo(trivia = { ColonRange = Some mColon1 }))))
+                    memberDefnForSet = Some(SynBinding(returnInfo = Some (SynBindingReturnInfo(trivia = { ColonRange = Some mColon2 }))))
+                )
+            ]))
+        ])
+    ]) ])) ->
+        assertRange (3,28) (3,29) mColon1
+        assertRange (3,52) (3,53) mColon2
+    | _ -> Assert.Fail $"Could not get valid AST, got {parseResults}"