diff --git a/src/ffi/unicodeobject.rs b/src/ffi/unicodeobject.rs
index 165e7aff2ed..de51d816012 100644
--- a/src/ffi/unicodeobject.rs
+++ b/src/ffi/unicodeobject.rs
@@ -143,14 +143,16 @@ extern "C" {
     #[cfg_attr(PyPy, link_name = "PyPyUnicode_FromOrdinal")]
     pub fn PyUnicode_FromOrdinal(ordinal: c_int) -> *mut PyObject;
     pub fn PyUnicode_ClearFreeList() -> c_int;
-    #[cfg(not(Py_LIMITED_API))]
+    #[cfg(any(not(Py_LIMITED_API), Py_3_10))]
     #[cfg(Py_3_7)]
+    #[cfg_attr(PyPy, link_name = "PyPyUnicode_AsUTF8AndSize")]
     pub fn PyUnicode_AsUTF8AndSize(unicode: *mut PyObject, size: *mut Py_ssize_t) -> *const c_char;
     #[cfg(not(Py_3_7))]
     #[cfg_attr(PyPy, link_name = "PyPyUnicode_AsUTF8AndSize")]
     pub fn PyUnicode_AsUTF8AndSize(unicode: *mut PyObject, size: *mut Py_ssize_t) -> *mut c_char;
     #[cfg(not(Py_LIMITED_API))]
     #[cfg(Py_3_7)]
+    #[cfg_attr(PyPy, link_name = "PyPyUnicode_AsUTF8")]
     pub fn PyUnicode_AsUTF8(unicode: *mut PyObject) -> *const c_char;
     #[cfg(not(Py_3_7))]
     #[cfg_attr(PyPy, link_name = "PyPyUnicode_AsUTF8")]
diff --git a/src/types/string.rs b/src/types/string.rs
index ee5d3314504..18b05c99f00 100644
--- a/src/types/string.rs
+++ b/src/types/string.rs
@@ -44,27 +44,26 @@ impl PyString {
     /// (containing unpaired surrogates).
     #[inline]
     pub fn to_str(&self) -> PyResult<&str> {
-        #[cfg(not(Py_LIMITED_API))]
-        unsafe {
-            let mut size: ffi::Py_ssize_t = 0;
-            let data = ffi::PyUnicode_AsUTF8AndSize(self.as_ptr(), &mut size) as *const u8;
-            if data.is_null() {
-                Err(PyErr::fetch(self.py()))
-            } else {
-                let slice = std::slice::from_raw_parts(data, size as usize);
-                Ok(std::str::from_utf8_unchecked(slice))
+        let utf8_slice = {
+            cfg_if::cfg_if! {
+                if #[cfg(any(not(Py_LIMITED_API), Py_3_10))] {
+                    // PyUnicode_AsUTF8AndSize only available on limited API from Python 3.10 and up.
+                    let mut size: ffi::Py_ssize_t = 0;
+                    let data = unsafe { ffi::PyUnicode_AsUTF8AndSize(self.as_ptr(), &mut size) };
+                    if data.is_null() {
+                        return Err(PyErr::fetch(self.py()));
+                    } else {
+                        unsafe { std::slice::from_raw_parts(data as *const u8, size as usize) }
+                    }
+                } else {
+                    let bytes = unsafe {
+                        self.py().from_owned_ptr_or_err::<PyBytes>(ffi::PyUnicode_AsUTF8String(self.as_ptr()))?
+                    };
+                    bytes.as_bytes()
+                }
             }
-        }
-        #[cfg(Py_LIMITED_API)]
-        unsafe {
-            let data = ffi::PyUnicode_AsUTF8String(self.as_ptr());
-            if data.is_null() {
-                Err(PyErr::fetch(self.py()))
-            } else {
-                let bytes = self.py().from_owned_ptr::<PyBytes>(data);
-                Ok(std::str::from_utf8_unchecked(bytes.as_bytes()))
-            }
-        }
+        };
+        Ok(unsafe { std::str::from_utf8_unchecked(utf8_slice) })
     }
 
     /// Converts the `PyString` into a Rust string.