diff --git a/clippy_lints/src/format_push_string.rs b/clippy_lints/src/format_push_string.rs
index de19c5ec20e..ebf5ab086dc 100644
--- a/clippy_lints/src/format_push_string.rs
+++ b/clippy_lints/src/format_push_string.rs
@@ -14,6 +14,12 @@ declare_clippy_lint! {
     /// ### Why is this bad?
     /// Introduces an extra, avoidable heap allocation.
     ///
+    /// ### Known problems
+    /// `format!` returns a `String` but `write!` returns a `Result`.
+    /// Thus you are forced to ignore the `Err` variant to achieve the same API.
+    ///
+    /// While using `write!` in the suggested way should never fail, this isn't necessarily clear to the programmer.
+    ///
     /// ### Example
     /// ```rust
     /// let mut s = String::new();
@@ -29,7 +35,7 @@ declare_clippy_lint! {
     /// ```
     #[clippy::version = "1.62.0"]
     pub FORMAT_PUSH_STRING,
-    perf,
+    restriction,
     "`format!(..)` appended to existing `String`"
 }
 declare_lint_pass!(FormatPushString => [FORMAT_PUSH_STRING]);
diff --git a/clippy_lints/src/lib.register_all.rs b/clippy_lints/src/lib.register_all.rs
index da26a3f0130..9afc714b11c 100644
--- a/clippy_lints/src/lib.register_all.rs
+++ b/clippy_lints/src/lib.register_all.rs
@@ -71,7 +71,6 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(format_args::TO_STRING_IN_FORMAT_ARGS),
     LintId::of(format_impl::PRINT_IN_FORMAT_IMPL),
     LintId::of(format_impl::RECURSIVE_FORMAT_IMPL),
-    LintId::of(format_push_string::FORMAT_PUSH_STRING),
     LintId::of(formatting::POSSIBLE_MISSING_COMMA),
     LintId::of(formatting::SUSPICIOUS_ASSIGNMENT_FORMATTING),
     LintId::of(formatting::SUSPICIOUS_ELSE_FORMATTING),
diff --git a/clippy_lints/src/lib.register_perf.rs b/clippy_lints/src/lib.register_perf.rs
index 6bf519c24e8..e1b90acb93c 100644
--- a/clippy_lints/src/lib.register_perf.rs
+++ b/clippy_lints/src/lib.register_perf.rs
@@ -7,7 +7,6 @@ store.register_group(true, "clippy::perf", Some("clippy_perf"), vec![
     LintId::of(escape::BOXED_LOCAL),
     LintId::of(format_args::FORMAT_IN_FORMAT_ARGS),
     LintId::of(format_args::TO_STRING_IN_FORMAT_ARGS),
-    LintId::of(format_push_string::FORMAT_PUSH_STRING),
     LintId::of(large_const_arrays::LARGE_CONST_ARRAYS),
     LintId::of(large_enum_variant::LARGE_ENUM_VARIANT),
     LintId::of(loops::MANUAL_MEMCPY),
diff --git a/clippy_lints/src/lib.register_restriction.rs b/clippy_lints/src/lib.register_restriction.rs
index 970e9db4772..88d43c8989f 100644
--- a/clippy_lints/src/lib.register_restriction.rs
+++ b/clippy_lints/src/lib.register_restriction.rs
@@ -21,6 +21,7 @@ store.register_group(true, "clippy::restriction", Some("clippy_restriction"), ve
     LintId::of(exhaustive_items::EXHAUSTIVE_STRUCTS),
     LintId::of(exit::EXIT),
     LintId::of(float_literal::LOSSY_FLOAT_LITERAL),
+    LintId::of(format_push_string::FORMAT_PUSH_STRING),
     LintId::of(if_then_some_else_none::IF_THEN_SOME_ELSE_NONE),
     LintId::of(implicit_return::IMPLICIT_RETURN),
     LintId::of(indexing_slicing::INDEXING_SLICING),