diff --git a/src/format/mod.rs b/src/format/mod.rs
index 90010c94f2..f8e917d474 100644
--- a/src/format/mod.rs
+++ b/src/format/mod.rs
@@ -523,7 +523,7 @@ pub enum Colon {
 }
 
 /// Prints an offset from UTC with the format defined in the `UtcOffsetFormat`.
-#[cfg(any(feature = "alloc", feature = "std"))]
+#[cfg(any(feature = "alloc", feature = "std", test))]
 impl UtcOffsetFormat {
     fn format(&self, result: &mut String, off: FixedOffset) -> fmt::Result {
         let off = off.local_minus_utc();
@@ -576,7 +576,7 @@ impl UtcOffsetFormat {
     }
 }
 
-#[cfg(any(feature = "alloc", feature = "std"))]
+#[cfg(any(feature = "alloc", feature = "std", test))]
 #[allow(clippy::too_many_arguments)]
 fn write_offsets(
     w: &mut impl Write,
@@ -1208,3 +1208,162 @@ impl FromStr for Month {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use crate::format::{Colon, OffsetPrecision, Pad, UtcOffsetFormat};
+    use crate::FixedOffset;
+
+    #[test]
+    fn test_offset_formatting() {
+        fn check_all(precision: OffsetPrecision, expected: [[&str; 7]; 12]) {
+            fn check(
+                precision: OffsetPrecision,
+                colons: Colon,
+                padding: Pad,
+                allow_zulu: bool,
+                offsets: [FixedOffset; 7],
+                expected: [&str; 7],
+            ) {
+                let offset_format = UtcOffsetFormat { precision, colons, allow_zulu, padding };
+                for (offset, expected) in offsets.iter().zip(expected.iter()) {
+                    let mut output = String::new();
+                    offset_format.format(&mut output, *offset).unwrap();
+                    assert_eq!(&output, expected);
+                }
+            }
+            // +03:45, -03:30, +11:00, -11:00:22, +02:34:26, -12:34:30, +00:00
+            let offsets = [
+                FixedOffset::east_opt(13_500).unwrap(),
+                FixedOffset::east_opt(-12_600).unwrap(),
+                FixedOffset::east_opt(39_600).unwrap(),
+                FixedOffset::east_opt(-39_622).unwrap(),
+                FixedOffset::east_opt(9266).unwrap(),
+                FixedOffset::east_opt(-45270).unwrap(),
+                FixedOffset::east_opt(0).unwrap(),
+            ];
+            check(precision, Colon::Colon, Pad::Zero, false, offsets, expected[0]);
+            check(precision, Colon::Colon, Pad::Zero, true, offsets, expected[1]);
+            check(precision, Colon::Colon, Pad::Space, false, offsets, expected[2]);
+            check(precision, Colon::Colon, Pad::Space, true, offsets, expected[3]);
+            check(precision, Colon::Colon, Pad::None, false, offsets, expected[4]);
+            check(precision, Colon::Colon, Pad::None, true, offsets, expected[5]);
+            check(precision, Colon::None, Pad::Zero, false, offsets, expected[6]);
+            check(precision, Colon::None, Pad::Zero, true, offsets, expected[7]);
+            check(precision, Colon::None, Pad::Space, false, offsets, expected[8]);
+            check(precision, Colon::None, Pad::Space, true, offsets, expected[9]);
+            check(precision, Colon::None, Pad::None, false, offsets, expected[10]);
+            check(precision, Colon::None, Pad::None, true, offsets, expected[11]);
+            // `Colon::Maybe` should format the same as `Colon::None`
+            check(precision, Colon::Maybe, Pad::Zero, false, offsets, expected[6]);
+            check(precision, Colon::Maybe, Pad::Zero, true, offsets, expected[7]);
+            check(precision, Colon::Maybe, Pad::Space, false, offsets, expected[8]);
+            check(precision, Colon::Maybe, Pad::Space, true, offsets, expected[9]);
+            check(precision, Colon::Maybe, Pad::None, false, offsets, expected[10]);
+            check(precision, Colon::Maybe, Pad::None, true, offsets, expected[11]);
+        }
+        check_all(
+            OffsetPrecision::Hours,
+            [
+                ["+03", "-03", "+11", "-11", "+02", "-12", "+00"],
+                ["+03", "-03", "+11", "-11", "+02", "-12", "Z"],
+                [" +3", " -3", "+11", "-11", " +2", "-12", " +0"],
+                [" +3", " -3", "+11", "-11", " +2", "-12", "Z"],
+                ["+3", "-3", "+11", "-11", "+2", "-12", "+0"],
+                ["+3", "-3", "+11", "-11", "+2", "-12", "Z"],
+                ["+03", "-03", "+11", "-11", "+02", "-12", "+00"],
+                ["+03", "-03", "+11", "-11", "+02", "-12", "Z"],
+                [" +3", " -3", "+11", "-11", " +2", "-12", " +0"],
+                [" +3", " -3", "+11", "-11", " +2", "-12", "Z"],
+                ["+3", "-3", "+11", "-11", "+2", "-12", "+0"],
+                ["+3", "-3", "+11", "-11", "+2", "-12", "Z"],
+            ],
+        );
+        check_all(
+            OffsetPrecision::Minutes,
+            [
+                ["+03:45", "-03:30", "+11:00", "-11:00", "+02:34", "-12:35", "+00:00"],
+                ["+03:45", "-03:30", "+11:00", "-11:00", "+02:34", "-12:35", "Z"],
+                [" +3:45", " -3:30", "+11:00", "-11:00", " +2:34", "-12:35", " +0:00"],
+                [" +3:45", " -3:30", "+11:00", "-11:00", " +2:34", "-12:35", "Z"],
+                ["+3:45", "-3:30", "+11:00", "-11:00", "+2:34", "-12:35", "+0:00"],
+                ["+3:45", "-3:30", "+11:00", "-11:00", "+2:34", "-12:35", "Z"],
+                ["+0345", "-0330", "+1100", "-1100", "+0234", "-1235", "+0000"],
+                ["+0345", "-0330", "+1100", "-1100", "+0234", "-1235", "Z"],
+                [" +345", " -330", "+1100", "-1100", " +234", "-1235", " +000"],
+                [" +345", " -330", "+1100", "-1100", " +234", "-1235", "Z"],
+                ["+345", "-330", "+1100", "-1100", "+234", "-1235", "+000"],
+                ["+345", "-330", "+1100", "-1100", "+234", "-1235", "Z"],
+            ],
+        );
+        #[rustfmt::skip]
+        check_all(
+            OffsetPrecision::Seconds,
+            [
+                ["+03:45:00", "-03:30:00", "+11:00:00", "-11:00:22", "+02:34:26", "-12:34:30", "+00:00:00"],
+                ["+03:45:00", "-03:30:00", "+11:00:00", "-11:00:22", "+02:34:26", "-12:34:30", "Z"],
+                [" +3:45:00", " -3:30:00", "+11:00:00", "-11:00:22", " +2:34:26", "-12:34:30", " +0:00:00"],
+                [" +3:45:00", " -3:30:00", "+11:00:00", "-11:00:22", " +2:34:26", "-12:34:30", "Z"],
+                ["+3:45:00", "-3:30:00", "+11:00:00", "-11:00:22", "+2:34:26", "-12:34:30", "+0:00:00"],
+                ["+3:45:00", "-3:30:00", "+11:00:00", "-11:00:22", "+2:34:26", "-12:34:30", "Z"],
+                ["+034500", "-033000", "+110000", "-110022", "+023426", "-123430", "+000000"],
+                ["+034500", "-033000", "+110000", "-110022", "+023426", "-123430", "Z"],
+                [" +34500", " -33000", "+110000", "-110022", " +23426", "-123430", " +00000"],
+                [" +34500", " -33000", "+110000", "-110022", " +23426", "-123430", "Z"],
+                ["+34500", "-33000", "+110000", "-110022", "+23426", "-123430", "+00000"],
+                ["+34500", "-33000", "+110000", "-110022", "+23426", "-123430", "Z"],
+            ],
+        );
+        check_all(
+            OffsetPrecision::OptionalMinutes,
+            [
+                ["+03:45", "-03:30", "+11", "-11", "+02:34", "-12:35", "+00"],
+                ["+03:45", "-03:30", "+11", "-11", "+02:34", "-12:35", "Z"],
+                [" +3:45", " -3:30", "+11", "-11", " +2:34", "-12:35", " +0"],
+                [" +3:45", " -3:30", "+11", "-11", " +2:34", "-12:35", "Z"],
+                ["+3:45", "-3:30", "+11", "-11", "+2:34", "-12:35", "+0"],
+                ["+3:45", "-3:30", "+11", "-11", "+2:34", "-12:35", "Z"],
+                ["+0345", "-0330", "+11", "-11", "+0234", "-1235", "+00"],
+                ["+0345", "-0330", "+11", "-11", "+0234", "-1235", "Z"],
+                [" +345", " -330", "+11", "-11", " +234", "-1235", " +0"],
+                [" +345", " -330", "+11", "-11", " +234", "-1235", "Z"],
+                ["+345", "-330", "+11", "-11", "+234", "-1235", "+0"],
+                ["+345", "-330", "+11", "-11", "+234", "-1235", "Z"],
+            ],
+        );
+        check_all(
+            OffsetPrecision::OptionalSeconds,
+            [
+                ["+03:45", "-03:30", "+11:00", "-11:00:22", "+02:34:26", "-12:34:30", "+00:00"],
+                ["+03:45", "-03:30", "+11:00", "-11:00:22", "+02:34:26", "-12:34:30", "Z"],
+                [" +3:45", " -3:30", "+11:00", "-11:00:22", " +2:34:26", "-12:34:30", " +0:00"],
+                [" +3:45", " -3:30", "+11:00", "-11:00:22", " +2:34:26", "-12:34:30", "Z"],
+                ["+3:45", "-3:30", "+11:00", "-11:00:22", "+2:34:26", "-12:34:30", "+0:00"],
+                ["+3:45", "-3:30", "+11:00", "-11:00:22", "+2:34:26", "-12:34:30", "Z"],
+                ["+0345", "-0330", "+1100", "-110022", "+023426", "-123430", "+0000"],
+                ["+0345", "-0330", "+1100", "-110022", "+023426", "-123430", "Z"],
+                [" +345", " -330", "+1100", "-110022", " +23426", "-123430", " +000"],
+                [" +345", " -330", "+1100", "-110022", " +23426", "-123430", "Z"],
+                ["+345", "-330", "+1100", "-110022", "+23426", "-123430", "+000"],
+                ["+345", "-330", "+1100", "-110022", "+23426", "-123430", "Z"],
+            ],
+        );
+        check_all(
+            OffsetPrecision::OptionalMinutesAndSeconds,
+            [
+                ["+03:45", "-03:30", "+11", "-11:00:22", "+02:34:26", "-12:34:30", "+00"],
+                ["+03:45", "-03:30", "+11", "-11:00:22", "+02:34:26", "-12:34:30", "Z"],
+                [" +3:45", " -3:30", "+11", "-11:00:22", " +2:34:26", "-12:34:30", " +0"],
+                [" +3:45", " -3:30", "+11", "-11:00:22", " +2:34:26", "-12:34:30", "Z"],
+                ["+3:45", "-3:30", "+11", "-11:00:22", "+2:34:26", "-12:34:30", "+0"],
+                ["+3:45", "-3:30", "+11", "-11:00:22", "+2:34:26", "-12:34:30", "Z"],
+                ["+0345", "-0330", "+11", "-110022", "+023426", "-123430", "+00"],
+                ["+0345", "-0330", "+11", "-110022", "+023426", "-123430", "Z"],
+                [" +345", " -330", "+11", "-110022", " +23426", "-123430", " +0"],
+                [" +345", " -330", "+11", "-110022", " +23426", "-123430", "Z"],
+                ["+345", "-330", "+11", "-110022", "+23426", "-123430", "+0"],
+                ["+345", "-330", "+11", "-110022", "+23426", "-123430", "Z"],
+            ],
+        );
+    }
+}