diff --git a/v3/clock/rfc822.go b/v3/clock/rfc822.go
index 446b58b4..c6a4dc25 100644
--- a/v3/clock/rfc822.go
+++ b/v3/clock/rfc822.go
@@ -16,6 +16,27 @@ func NewRFC822Time(t Time) RFC822Time {
 	return RFC822Time{Time: t.Truncate(Second)}
 }
 
+// ParseRFC822Time parses an RFC822 time string.
+func ParseRFC822Time(s string) (Time, error) {
+	t, err := Parse("Mon, 2 Jan 2006 15:04:05 MST", s)
+	if err == nil {
+		return t, nil
+	}
+	if parseErr, ok := err.(*ParseError); !ok || parseErr.LayoutElem != "MST" {
+		return Time{}, parseErr
+	}
+	if t, err = Parse("Mon, 2 Jan 2006 15:04:05 -0700", s); err == nil {
+		return t, nil
+	}
+	if parseErr, ok := err.(*ParseError); !ok || parseErr.LayoutElem != "" {
+		return Time{}, parseErr
+	}
+	if t, err = Parse("Mon, 2 Jan 2006 15:04:05 -0700 (MST)", s); err == nil {
+		return t, nil
+	}
+	return Time{}, err
+}
+
 // NewRFC822Time creates RFC822Time from a Unix timestamp (seconds from Epoch).
 func NewRFC822TimeFromUnix(timestamp int64) RFC822Time {
 	return RFC822Time{Time: Unix(timestamp, 0).UTC()}
@@ -30,15 +51,11 @@ func (t *RFC822Time) UnmarshalJSON(s []byte) error {
 	if err != nil {
 		return err
 	}
-	if t.Time, err = Parse("Mon, 2 Jan 2006 15:04:05 MST", q); err == nil {
-		return nil
-	}
-	if err, ok := err.(*ParseError); !ok || err.LayoutElem != "MST" {
-		return err
-	}
-	if t.Time, err = Parse("Mon, 2 Jan 2006 15:04:05 -0700", q); err != nil {
+	parsed, err := ParseRFC822Time(q)
+	if err != nil {
 		return err
 	}
+	t.Time = parsed
 	return nil
 }
 
diff --git a/v3/clock/rfc822_test.go b/v3/clock/rfc822_test.go
index 49bca502..ae5761d4 100644
--- a/v3/clock/rfc822_test.go
+++ b/v3/clock/rfc822_test.go
@@ -91,6 +91,22 @@ func TestRFC822Unmarshaling(t *testing.T) {
 		inRFC822:   "Sun, 1 Sep 2019 11:20:07 +0300",
 		outRFC3339: "2019-09-01T11:20:07+03:00",
 		outRFC822:  "Sun, 01 Sep 2019 11:20:07 MSK",
+	}, {
+		inRFC822:   "Sun, 1 Sep 2019 11:20:07 UTC",
+		outRFC3339: "2019-09-01T11:20:07Z",
+		outRFC822:  "Sun, 01 Sep 2019 11:20:07 UTC",
+	}, {
+		inRFC822:   "Sun, 1 Sep 2019 11:20:07 UTC",
+		outRFC3339: "2019-09-01T11:20:07Z",
+		outRFC822:  "Sun, 01 Sep 2019 11:20:07 UTC",
+	}, {
+		inRFC822:   "Sun, 1 Sep 2019 11:20:07 GMT",
+		outRFC3339: "2019-09-01T11:20:07Z",
+		outRFC822:  "Sun, 01 Sep 2019 11:20:07 GMT",
+	}, {
+		inRFC822:   "Fri, 21 Nov 1997 09:55:06 -0600 (MDT)",
+		outRFC3339: "1997-11-21T09:55:06-06:00",
+		outRFC822:  "Fri, 21 Nov 1997 09:55:06 MDT",
 	}} {
 		tcDesc := fmt.Sprintf("Test case #%d: %v", i, tc)
 		var ts testStruct
@@ -113,10 +129,10 @@ func TestRFC822UnmarshalingError(t *testing.T) {
 		outError  string
 	}{{
 		inEncoded: `{"ts": "Thu, 29 Aug 2019 11:20:07"}`,
-		outError:  `parsing time "Thu, 29 Aug 2019 11:20:07" as "Mon, 02 Jan 2006 15:04:05 -0700": cannot parse "" as "-0700"`,
+		outError:  `parsing time "Thu, 29 Aug 2019 11:20:07" as "Mon, 2 Jan 2006 15:04:05 -0700": cannot parse "" as "-0700"`,
 	}, {
 		inEncoded: `{"ts": "foo"}`,
-		outError:  `parsing time "foo" as "Mon, 02 Jan 2006 15:04:05 MST": cannot parse "foo" as "Mon"`,
+		outError:  `parsing time "foo" as "Mon, 2 Jan 2006 15:04:05 MST": cannot parse "foo" as "Mon"`,
 	}, {
 		inEncoded: `{"ts": 42}`,
 		outError:  "invalid syntax",