diff --git a/.spelling b/.spelling
index 533d210b07..7726adfc7d 100644
--- a/.spelling
+++ b/.spelling
@@ -85,6 +85,8 @@ mutexes
 nodewallet
 notarising
 OpenRPC
+perp
+perps
 phish
 Prometheus
 proto
diff --git a/CHANGELOG.md b/CHANGELOG.md
index cd24bdd8f5..5df0fa760a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,7 @@
 
 - [9940](https://github.com/vegaprotocol/vega/issues/9940) - Do not assume stop order is valid when generating ids up front.
 - [10103](https://github.com/vegaprotocol/vega/issues/10103) - List ledgers `API` returns bad error when filtering by transfer type only.
+- [10121](https://github.com/vegaprotocol/vega/issues/10121) - Assure `EstimatePosition` API works correctly with sparse perps data
 
 ## 0.73.4
 
diff --git a/datanode/api/trading_data_v2.go b/datanode/api/trading_data_v2.go
index 486eb5c7f8..66d8d30aca 100644
--- a/datanode/api/trading_data_v2.go
+++ b/datanode/api/trading_data_v2.go
@@ -3243,7 +3243,11 @@ func (t *TradingDataServiceV2) EstimatePosition(ctx context.Context, req *v2.Est
 				if err != nil {
 					return nil, formatE(fmt.Errorf("can't parse funding payment from perpetual product data: %s", perpData.FundingPayment), err)
 				}
-				if !fundingPayment.IsZero() {
+				fundingRate, err := num.DecimalFromString(perpData.FundingRate)
+				if err != nil {
+					return nil, formatE(fmt.Errorf("can't parse funding rate from perpetual product data: %s", perpData.FundingRate), err)
+				}
+				if !fundingPayment.IsZero() && !fundingRate.IsZero() {
 					marginFactorScaledFundingPaymentPerUnitPosition = factor.Mul(fundingPayment)
 				}
 			}