diff --git a/CHANGELOG.md b/CHANGELOG.md
index fe2d3f2..170757a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,8 @@ v3.1.0 (in development)
 - When `git describe` fails to retrieve a tag, the resulting log/error message
   now includes all options passed to the command (based on contribution by
   [@jenshnielsen](https://github.com/jenshnielsen))
+- When `hg log` fails to retrieve a tag, the resulting log/error message now
+  includes the tag pattern passed to `latesttag()`, if any
 
 v3.0.0 (2023-12-13)
 -------------------
diff --git a/docs/changelog.rst b/docs/changelog.rst
index 77b0714..3ec9b7f 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -8,6 +8,8 @@ v3.1.0 (in development)
 - When :command:`git describe` fails to retrieve a tag, the resulting log/error
   message now includes all options passed to the command (based on contribution
   by `@jenshnielsen <https://github.com/jenshnielsen>`_)
+- When :command:`hg log` fails to retrieve a tag, the resulting log/error
+  message now includes the tag pattern passed to ``latesttag()``, if any
 
 
 v3.0.0 (2023-12-13)
diff --git a/src/versioningit/hg.py b/src/versioningit/hg.py
index 538e8df..1360670 100644
--- a/src/versioningit/hg.py
+++ b/src/versioningit/hg.py
@@ -102,15 +102,23 @@ def describe_hg(*, project_dir: str | Path, params: dict[str, Any]) -> VCSDescri
     else:
         dirty = False
     if tag == "null":
+        if pattern is None:
+            suffix = ""
+        else:
+            suffix = f" (pattern = {pattern!r})"
+        # Unlike the Git methods, don't show the full `hg log` command run, as
+        # shlex.quote() on `--template` arguments returns something *ugly*.
         if default_tag is not None:
-            log.info("No latest tag; falling back to default tag %r", default_tag)
+            log.info(
+                "No latest tag%s; falling back to default tag %r", suffix, default_tag
+            )
             tag = default_tag
             # Act as though the first commit is the one with the default tag,
             # i.e., don't count it (unless there is no first commit, of course)
             if distance > 0:
                 distance -= 1
         else:
-            raise NoTagError("No latest tag in Mercurial repository")
+            raise NoTagError(f"No latest tag in Mercurial repository{suffix}")
     if distance and dirty:
         state = "distance-dirty"
     elif distance:
diff --git a/test/data/repos/errors/hg-no-tag.json b/test/data/repos/errors/hg-no-tag.json
new file mode 100644
index 0000000..f70dcfb
--- /dev/null
+++ b/test/data/repos/errors/hg-no-tag.json
@@ -0,0 +1,4 @@
+{
+    "type": "NoTagError",
+    "message": "No latest tag in Mercurial repository (pattern = 're:^v')"
+}
diff --git a/test/data/repos/errors/hg-no-tag.zip b/test/data/repos/errors/hg-no-tag.zip
new file mode 100644
index 0000000..dbe99e1
Binary files /dev/null and b/test/data/repos/errors/hg-no-tag.zip differ
diff --git a/test/data/repos/hg/default-tag-fallback.fields.json b/test/data/repos/hg/default-tag-fallback.fields.json
new file mode 100644
index 0000000..0ed570c
--- /dev/null
+++ b/test/data/repos/hg/default-tag-fallback.fields.json
@@ -0,0 +1,8 @@
+{
+    "build_date": "2038-01-19 03:14:07+00:00",
+    "distance": 3,
+    "rev": "5296453555c9",
+    "revision": "5296453555c92c22bab469752758a549e297c922",
+    "vcs": "h",
+    "vcs_name": "hg"
+}
diff --git a/test/data/repos/hg/default-tag-fallback.json b/test/data/repos/hg/default-tag-fallback.json
new file mode 100644
index 0000000..be4ec96
--- /dev/null
+++ b/test/data/repos/hg/default-tag-fallback.json
@@ -0,0 +1,10 @@
+{
+    "version": "0.0.0.post3+h5296453555c9",
+    "next_version": "0.1.0",
+    "logmsgs": [
+        {
+            "level": "INFO",
+            "message": "No latest tag (pattern = 're:^v'); falling back to default tag 'v0.0.0'"
+        }
+    ]
+}
diff --git a/test/data/repos/hg/default-tag-fallback.zip b/test/data/repos/hg/default-tag-fallback.zip
new file mode 100644
index 0000000..39bf79b
Binary files /dev/null and b/test/data/repos/hg/default-tag-fallback.zip differ
diff --git a/test/test_methods/test_hg.py b/test/test_methods/test_hg.py
index 79c7029..4ed77a1 100644
--- a/test/test_methods/test_hg.py
+++ b/test/test_methods/test_hg.py
@@ -39,6 +39,12 @@ class HGFields(BaseModel):
         ("distance", {}, "v0.1.0", "distance"),
         ("distance-dirty", {}, "v0.1.0", "distance-dirty"),
         ("default-tag", {"default-tag": "v0.0.0"}, "v0.0.0", "distance"),
+        (
+            "default-tag-fallback",
+            {"default-tag": "v0.0.0", "pattern": "re:^v"},
+            "v0.0.0",
+            "distance",
+        ),
         ("pattern", {"pattern": r"re:^v"}, "v0.1.0", "distance"),
     ],
 )