diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3c6f8242005..f8422ef6e92 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -22,6 +22,8 @@
 
 #### :bug: Bug fix
 
+- Fix formatter breaking the opening brace of a functor module type's result signature onto a new line (e.g. `module Make: Pattern => {`). https://github.com/rescript-lang/rescript/pull/8519
+
 #### :memo: Documentation
 
 #### :nail_care: Polish
diff --git a/compiler/syntax/src/res_printer.ml b/compiler/syntax/src/res_printer.ml
index dd15d0bb630..a56837fb1b0 100644
--- a/compiler/syntax/src/res_printer.ml
+++ b/compiler/syntax/src/res_printer.ml
@@ -931,11 +931,19 @@ and print_mod_type ~state mod_type cmt_tbl =
         if Parens.mod_type_functor_return return_type then add_parens doc
         else doc
       in
+      (* When the functor result is a signature, keep its opening brace on the
+         same line as `=>` instead of breaking onto a new line, mirroring how
+         module-expression functors are printed (see print_mod_functor). *)
+      let arrow_sep =
+        match return_type.pmty_desc with
+        | Pmty_signature _ -> Doc.space
+        | _ -> Doc.line
+      in
       Doc.group
         (Doc.concat
            [
              parameters_doc;
-             Doc.group (Doc.concat [Doc.text " =>"; Doc.line; return_doc]);
+             Doc.group (Doc.concat [Doc.text " =>"; arrow_sep; return_doc]);
            ])
     | Pmty_typeof mod_expr ->
       Doc.concat
diff --git a/tests/syntax_tests/data/printer/modExpr/expected/structure.res.txt b/tests/syntax_tests/data/printer/modExpr/expected/structure.res.txt
index a958790e769..14e1ecd1f67 100644
--- a/tests/syntax_tests/data/printer/modExpr/expected/structure.res.txt
+++ b/tests/syntax_tests/data/printer/modExpr/expected/structure.res.txt
@@ -52,8 +52,7 @@ module M3: {
   include M'
 }
 
-module G0: (X: {}) =>
-{
+module G0: (X: {}) => {
   module N': {
     let x: int
   }
diff --git a/tests/syntax_tests/data/printer/modType/expected/functor.res.txt b/tests/syntax_tests/data/printer/modType/expected/functor.res.txt
index 311a32c474a..2af4bf0c652 100644
--- a/tests/syntax_tests/data/printer/modType/expected/functor.res.txt
+++ b/tests/syntax_tests/data/printer/modType/expected/functor.res.txt
@@ -13,7 +13,17 @@ module type Functor = (@attr1 SetLike, @attr2 BtreeLike) => @attr3 NeoTree
 module type Functor = (SetLike => Set) with type t = A.t
 module type Functor = SetLike => (Set with type t = A.t)
 
-module type B = () =>
-{
+module type B = () => {
 
 }
+
+module type ThisIsAVeryLongFunctorModuleTypeNameThatExceedsTheEightyCharacterLimit = Pattern => {
+  let fmt: event => string
+}
+
+module type SecondVeryLongFunctorModuleTypeNameWithMultipleShortParameters = (A, B) => {
+  let x: int
+}
+
+module type YetAnotherVeryLongFunctorModuleTypeNameHere = SomeVeryLongParameterModuleTypeName =>
+SomeVeryLongResultingModuleTypeName
diff --git a/tests/syntax_tests/data/printer/modType/expected/functorInterface.resi.txt b/tests/syntax_tests/data/printer/modType/expected/functorInterface.resi.txt
new file mode 100644
index 00000000000..8dcc62c8735
--- /dev/null
+++ b/tests/syntax_tests/data/printer/modType/expected/functorInterface.resi.txt
@@ -0,0 +1,28 @@
+module Make: Pattern => {
+  let fmt: event => string
+}
+
+module Curried: (A, B) => {
+  let x: int
+}
+
+module Nested: (A, B) => {
+  let y: int
+}
+
+module Empty: () => {}
+
+module ResultIdent: A => B
+
+module ResultWith: A => (B with type t = int)
+
+module ThisIsAVeryLongFunctorModuleTypeNameThatExceedsTheEightyCharacterLimit: Pattern => {
+  let fmt: event => string
+}
+
+module SecondVeryLongFunctorModuleTypeNameWithMultipleShortParameters: (A, B) => {
+  let x: int
+}
+
+module YetAnotherVeryLongFunctorModuleTypeNameHere: SomeVeryLongParameterModuleTypeName =>
+SomeVeryLongResultingModuleTypeName
diff --git a/tests/syntax_tests/data/printer/modType/functor.res b/tests/syntax_tests/data/printer/modType/functor.res
index 9149ed582c6..cea142cee36 100644
--- a/tests/syntax_tests/data/printer/modType/functor.res
+++ b/tests/syntax_tests/data/printer/modType/functor.res
@@ -16,4 +16,14 @@ module type Functor = SetLike => (Set with type t = A.t)
 
 module type B = () => {
 
-}
\ No newline at end of file
+}
+
+module type ThisIsAVeryLongFunctorModuleTypeNameThatExceedsTheEightyCharacterLimit = Pattern => {
+  let fmt: event => string
+}
+
+module type SecondVeryLongFunctorModuleTypeNameWithMultipleShortParameters = (A, B) => {
+  let x: int
+}
+
+module type YetAnotherVeryLongFunctorModuleTypeNameHere = SomeVeryLongParameterModuleTypeName => SomeVeryLongResultingModuleTypeName
\ No newline at end of file
diff --git a/tests/syntax_tests/data/printer/modType/functorInterface.resi b/tests/syntax_tests/data/printer/modType/functorInterface.resi
new file mode 100644
index 00000000000..07a8aa5a108
--- /dev/null
+++ b/tests/syntax_tests/data/printer/modType/functorInterface.resi
@@ -0,0 +1,27 @@
+module Make: Pattern => {
+  let fmt: event => string
+}
+
+module Curried: (A, B) => {
+  let x: int
+}
+
+module Nested: A => B => {
+  let y: int
+}
+
+module Empty: () => {}
+
+module ResultIdent: A => B
+
+module ResultWith: A => (B with type t = int)
+
+module ThisIsAVeryLongFunctorModuleTypeNameThatExceedsTheEightyCharacterLimit: Pattern => {
+  let fmt: event => string
+}
+
+module SecondVeryLongFunctorModuleTypeNameWithMultipleShortParameters: (A, B) => {
+  let x: int
+}
+
+module YetAnotherVeryLongFunctorModuleTypeNameHere: SomeVeryLongParameterModuleTypeName => SomeVeryLongResultingModuleTypeName