diff --git a/bfxapi/rest/bfx_rest.py b/bfxapi/rest/bfx_rest.py
index fba9b60..7100464 100644
--- a/bfxapi/rest/bfx_rest.py
+++ b/bfxapi/rest/bfx_rest.py
@@ -869,7 +869,7 @@ class BfxRest:
         if price_trailing != None:
             payload['price_trailing'] = str(price_trailing)
         if time_in_force != None:
-            payload['time_in_force'] = str(time_in_force)
+            payload['tif'] = str(time_in_force)
         if leverage != None:
             payload["lev"] = str(leverage)
         flags = calculate_order_flags(