diff --git a/CHANGELOG.md b/CHANGELOG.md
index ee3f901383..03eb1a1d07 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -70,6 +70,7 @@
 - [10950](https://github.com/vegaprotocol/vega/issues/10950) - Fix bug that caused cancelled liquidity provisions to stick around after opening auction.
 - [10975](https://github.com/vegaprotocol/vega/issues/10975) - Fix marshaller for stop order rejection error.
 - [10973](https://github.com/vegaprotocol/vega/issues/10973) - Avoid entering an auction or doing mark-to-market before market entered opening auction or after it is in a terminal state.
+- [11252](https://github.com/vegaprotocol/vega/issues/11252) - Treat no position as zero position when calculating stop order overrides.
 - [10969](https://github.com/vegaprotocol/vega/issues/10969) - Ensure teams statistics are computed from team rewards.
 - [10962](https://github.com/vegaprotocol/vega/issues/10962) - Fix `lastFeeDistribution` time in snapshot.
 - [10974](https://github.com/vegaprotocol/vega/issues/10974) - Target stake for spot should not consider position factor.
diff --git a/core/execution/future/market.go b/core/execution/future/market.go
index d5327ec2e0..5bb8a65dce 100644
--- a/core/execution/future/market.go
+++ b/core/execution/future/market.go
@@ -4145,10 +4145,13 @@ func (m *Market) submitStopOrders(
 		if v.Status == status {
 			if v.SizeOverrideSetting == types.StopOrderSizeOverrideSettingPosition {
 				// Update the order size to match that of the party's position
-				pos, _ := m.position.GetPositionByPartyID(v.Party)
+				var pos int64
+				if position, ok := m.position.GetPositionByPartyID(v.Party); ok {
+					pos = position.Size()
+				}
 
 				// Scale this size if required
-				scaledPos := num.DecimalFromInt64(pos.Size())
+				scaledPos := num.DecimalFromInt64(pos)
 				if v.SizeOverrideValue != nil {
 					scaledPos = scaledPos.Mul(v.SizeOverrideValue.PercentageSize)
 					scaledPos = scaledPos.Round(0)