diff --git a/bqetl_project.yaml b/bqetl_project.yaml
index ecd9b221ae..ad605c0f65 100644
--- a/bqetl_project.yaml
+++ b/bqetl_project.yaml
@@ -296,6 +296,7 @@ generate:
     - sql/moz-fx-data-shared-prod/org_mozilla_ios_focus_derived/baseline_clients_last_seen_v1/bigconfig.yml
     - sql/moz-fx-data-shared-prod/org_mozilla_social_nightly_derived/baseline_clients_last_seen_v1/checks.sql
     - sql/moz-fx-data-shared-prod/net_thunderbird_android_daily_derived/baseline_clients_last_seen_v1/checks.sql
+    - sql/moz-fx-data-shared-prod/net_thunderbird_android_derived/baseline_clients_last_seen_v1/checks.sql
     skip_apps:
     - mlhackweek_search
     - moso_mastodon_android
diff --git a/sql/moz-fx-data-shared-prod/net_thunderbird_android_derived/baseline_clients_last_seen_v1/checks.sql b/sql/moz-fx-data-shared-prod/net_thunderbird_android_derived/baseline_clients_last_seen_v1/checks.sql
new file mode 100644
index 0000000000..9f6de83942
--- /dev/null
+++ b/sql/moz-fx-data-shared-prod/net_thunderbird_android_derived/baseline_clients_last_seen_v1/checks.sql
@@ -0,0 +1,83 @@
+#warn
+{{ is_unique(["client_id"], where="submission_date = @submission_date") }}
+
+#warn
+{{ not_null([
+  "submission_date",
+  "client_id",
+  "sample_id",
+  "first_seen_date",
+  "days_seen_bits",
+  "days_active_bits",
+  "days_created_profile_bits",
+  "days_seen_session_start_bits",
+  "days_seen_session_end_bits"
+  ], where="submission_date = @submission_date") }}
+
+#warn
+SELECT
+  IF(
+    COUNTIF(normalized_channel NOT IN ("nightly", "aurora", "release", "Other", "beta", "esr")) > 0,
+    ERROR("Unexpected values for field normalized_channel detected."),
+    NULL
+  )
+FROM
+  `{{ project_id }}.{{ dataset_id }}.{{ table_name }}`
+WHERE
+  submission_date = @submission_date;
+
+#warn
+{{ matches_pattern(column="country", pattern="^[A-Z]{2}$", where="submission_date = @submission_date") }}
+
+#warn
+{{ value_length(column="client_id", expected_length=36, where="submission_date = @submission_date") }}
+
+#fail
+WITH daily AS (
+  SELECT
+    submission_date,
+    COUNT(DISTINCT client_id) AS client_count
+  FROM
+    `moz-fx-data-shared-prod.net_thunderbird_android_derived.baseline_clients_daily_v1`
+  WHERE
+    submission_date = @submission_date
+    AND sample_id IS NOT NULL
+  GROUP BY
+    submission_date
+),
+last_seen AS (
+  SELECT
+    submission_date,
+    COUNT(DISTINCT client_id) AS client_count
+  FROM
+    `moz-fx-data-shared-prod.net_thunderbird_android_derived.baseline_clients_last_seen_v1`
+  WHERE
+    submission_date = @submission_date
+    AND mozfun.bits28.days_since_seen(days_seen_bits) = 0
+  GROUP BY
+    submission_date
+),
+check_results AS (
+  SELECT
+    1 - (last_seen.client_count / daily.client_count) AS difference_perc
+  FROM
+    daily
+  LEFT JOIN
+    last_seen
+    USING (submission_date)
+)
+SELECT
+  IF(
+    ABS((SELECT difference_perc FROM check_results)) > 0.001,
+    ERROR(
+      CONCAT(
+        "Results don't match by > 1%, baseline_clients_daily table has ",
+        STRING(((SELECT submission_date FROM daily))),
+        ": ",
+        ABS((SELECT client_count FROM daily)),
+        ". baseline_clients_last_seen has ",
+        IFNULL(((SELECT client_count FROM last_seen)), 0)
+      )
+    ),
+    NULL
+  );