diff --git a/CHANGES.md b/CHANGES.md
index 04ceb10ae..227e0c924 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -2,8 +2,10 @@
 
 ## __NEXT__
 
+* `augur refine` will now warn when building a time tree if sequence IDs in the tree don't match metadata IDs, suggesting the use of `--metadata-id-columns` to explicitly set the correct ID column. [#1902][] (@corneliusroemer)
 * `augur curate apply-record-annotations` will now warn if an annotation was unnecessary, often indicative of the upstream data being updated. [#1893][] (@jameshadfield)
 
+[#1902]: https://github.com/nextstrain/augur/pull/1902
 [#1893]: https://github.com/nextstrain/augur/pull/1893
 
 ## 31.5.0 (17 September 2025)
diff --git a/augur/refine.py b/augur/refine.py
index 183198e15..565b64608 100644
--- a/augur/refine.py
+++ b/augur/refine.py
@@ -309,6 +309,16 @@ def run(args):
         except InvalidYearBounds as error:
             raise AugurError(f"Invalid value for --year-bounds: {error}")
 
+        terminal_names = {n.name for n in T.get_terminals()}
+        matched_ids = terminal_names & set(dates.keys())
+
+        if len(matched_ids) < len(terminal_names) * 0.5:
+            print(f"\nWARNING: For {len(terminal_names)} sequence IDs, only {len(matched_ids)} corresponding metadata rows could be matched.", file=sys.stderr)
+            print(f"  Metadata has {len(dates)} entries in total.", file=sys.stderr)
+            print(f"  Metadata is using '{metadata_object.id_column}' as the ID column.", file=sys.stderr)
+            print(f"  You may need to explicitly set the metadata ID column using --metadata-id-columns.", file=sys.stderr)
+            print(f"  By default, the columns {DEFAULT_ID_COLUMNS} are tried in order.\n", file=sys.stderr)
+
         # save input state string for later export
         for n in T.get_terminals():
             if n.name in metadata.index and METADATA_DATE_COLUMN in metadata.columns:
diff --git a/tests/functional/refine/cram/metadata-id-mismatch.t b/tests/functional/refine/cram/metadata-id-mismatch.t
new file mode 100644
index 000000000..c28e2fb9c
--- /dev/null
+++ b/tests/functional/refine/cram/metadata-id-mismatch.t
@@ -0,0 +1,50 @@
+Setup
+
+  $ source "$TESTDIR"/_setup.sh
+
+Create metadata with mismatched IDs by adding a 'name' column with correct IDs
+and replacing the 'strain' column with wrong IDs.
+
+  $ awk -F'\t' 'BEGIN {OFS="\t"} NR==1 {print $0,"name"} NR>1 {print "wrong_id_"NR,$2,$3,$4,$5,$6,$7,$8,$9,$10,$11,$12,$13,$14,$15,$1}' \
+  >   "$TESTDIR/../data/metadata.tsv" > metadata_mismatch.tsv
+
+Try building a time tree with mismatched sequence and metadata IDs.
+This should produce a warning because the default 'strain' column has wrong IDs.
+The command will fail due to insufficient matching IDs, so redirect stdout.
+
+  $ ${AUGUR} refine \
+  >  --tree "$TESTDIR/../data/tree_raw.nwk" \
+  >  --alignment "$TESTDIR/../data/aligned.fasta" \
+  >  --metadata metadata_mismatch.tsv \
+  >  --output-tree tree_mismatch.nwk \
+  >  --output-node-data branch_lengths_mismatch.json \
+  >  --timetree \
+  >  --seed 314159 > /dev/null
+  
+  WARNING: For 11 sequence IDs, only 0 corresponding metadata rows could be matched.
+    Metadata has 12 entries in total.
+    Metadata is using 'strain' as the ID column.
+    You may need to explicitly set the metadata ID column using --metadata-id-columns.
+    By default, the columns ('strain', 'name') are tried in order.
+  
+  ERROR: ERROR: ALMOST NO VALID DATE CONSTRAINTS
+  
+  
+  ERROR from TreeTime: This error is most likely due to a problem with your input data.
+  Please check your input data and try again. If you continue to have problems, please open a new issue including
+  the original command and the error above:  <https://github.com/nextstrain/augur/issues/new/choose>
+  
+  [2]
+
+Now try with the correct ID column specified.
+This should work without the ID mismatch warning.
+
+  $ ${AUGUR} refine \
+  >  --tree "$TESTDIR/../data/tree_raw.nwk" \
+  >  --alignment "$TESTDIR/../data/aligned.fasta" \
+  >  --metadata metadata_mismatch.tsv \
+  >  --metadata-id-columns name \
+  >  --output-tree tree_correct.nwk \
+  >  --output-node-data branch_lengths_correct.json \
+  >  --timetree \
+  >  --seed 314159 > /dev/null