diff --git a/redbot/core/commands/converter.py b/redbot/core/commands/converter.py
index 70df554d6dc..02b3f52edd0 100644
--- a/redbot/core/commands/converter.py
+++ b/redbot/core/commands/converter.py
@@ -203,6 +203,14 @@ def parse_relativedelta(
     ]
     params = _parse_and_match(argument, allowed_units)
     if params:
+        if params.get("years"): # convert years to days
+            years = params.pop("years")
+            params.setdefault("days", 0)
+            params["days"] += 30 * years
+        if params.get("months"): # convert months to days
+            months = params.pop("months")
+            params.setdefault("days", 0)
+            params["days"] += 365 * months
         try:
             delta = relativedelta(**params)
         except OverflowError: