diff --git a/ethosu/vela/register_command_stream_generator.py b/ethosu/vela/register_command_stream_generator.py
index fb705b9..3b552e0 100644
--- a/ethosu/vela/register_command_stream_generator.py
+++ b/ethosu/vela/register_command_stream_generator.py
@@ -718,19 +718,39 @@
                 ofm_scale, shift = scaling.elementwise_mul_scale(input_scale, input2_scale, output_scale)
             emit.cmd1_with_offset(cmd1.NPU_SET_OFM_SCALE, ofm_scale, shift)
         else:  # Add/Sub
+            bitdepth = npu_op.ifm.data_type.size_in_bits()
+            use_advanced_scaling = False
             if None in (input_scale, input2_scale, output_scale):
                 opa_scale = opb_scale = ofm_scale = 1
                 opa_shift = shift = 0
                 if npu_op.rescale is not None:
                     ofm_scale, shift = npu_op.rescale
+            elif input_scale == input2_scale and bitdepth == 16:
+                opa_scale, opb_scale, ofm_scale, shift = scaling.simplified_elementwise_add_sub_scale(
+                    input_scale, input2_scale, output_scale
+                )
+                # align the double rounding with that of advanced scaling
+                opa_scale /= 2
+                opb_scale /= 2
+                shift -= 1
+                opa_shift = 0  # Unused for this case
             elif input_scale == input2_scale:
                 opa_scale, opb_scale, ofm_scale, shift = scaling.simplified_elementwise_add_sub_scale(
                     input_scale, input2_scale, output_scale
                 )
                 opa_shift = 0  # Unused for this case
+                # For 8 bit we can't guarantee double rounding with simplified scaling will always be
+                # the same as with advanced scaling due to different shifts. When the ofm scale fulfils
+                # the following we know that double rounding will have no effect for advanced scaling
+                # no matter the input, so we can safely use simplified scaling with double rounding disabled.
+                use_advanced_scaling = int(ofm_scale) & 0xFFF != 0
+                if not use_advanced_scaling:
+                    npu_op.rounding_mode = NpuRoundingMode.NATURAL
             else:
-                # Use advanced implementation only when input scales differ
-                bitdepth = npu_op.ifm.data_type.size_in_bits()
+                use_advanced_scaling = True
+            if use_advanced_scaling:
+                # Use advanced implementation only when input/output scales differ,
+                # or when we can't guarantee the absence of rounding errors
                 (opa_scale, opa_shift, ofm_scale, shift, op_to_scale,) = scaling.advanced_elementwise_add_sub_scale(
                     input_scale, input2_scale, output_scale, bitdepth
                 )