diff --git a/partiql-planner/src/test/kotlin/org/partiql/planner/internal/typer/PlanTyperTestsPorted.kt b/partiql-planner/src/test/kotlin/org/partiql/planner/internal/typer/PlanTyperTestsPorted.kt
index 78f25c0480..090a444efb 100644
--- a/partiql-planner/src/test/kotlin/org/partiql/planner/internal/typer/PlanTyperTestsPorted.kt
+++ b/partiql-planner/src/test/kotlin/org/partiql/planner/internal/typer/PlanTyperTestsPorted.kt
@@ -3317,8 +3317,8 @@ class PlanTyperTestsPorted {
                             "min_b" to StaticType.INT4.asNullable(),
                             "max_a" to StaticType.INT4.asNullable(),
                             "max_b" to StaticType.INT4.asNullable(),
-                            "avg_a" to StaticType.INT4.asNullable(),
-                            "avg_b" to StaticType.INT4.asNullable(),
+                            "avg_a" to StaticType.DECIMAL.asNullable(),
+                            "avg_b" to StaticType.DECIMAL.asNullable(),
                         ),
                         contentClosed = true,
                         constraints = setOf(
diff --git a/partiql-spi/src/main/kotlin/org/partiql/spi/connector/sql/builtins/AggAvg.kt b/partiql-spi/src/main/kotlin/org/partiql/spi/connector/sql/builtins/AggAvg.kt
index cf110ab6a3..1287a7f011 100644
--- a/partiql-spi/src/main/kotlin/org/partiql/spi/connector/sql/builtins/AggAvg.kt
+++ b/partiql-spi/src/main/kotlin/org/partiql/spi/connector/sql/builtins/AggAvg.kt
@@ -10,6 +10,7 @@ import org.partiql.spi.fn.FnExperimental
 import org.partiql.spi.fn.FnParameter
 import org.partiql.value.PartiQLValueExperimental
 import org.partiql.value.PartiQLValueType.ANY
+import org.partiql.value.PartiQLValueType.DECIMAL
 import org.partiql.value.PartiQLValueType.DECIMAL_ARBITRARY
 import org.partiql.value.PartiQLValueType.FLOAT32
 import org.partiql.value.PartiQLValueType.FLOAT64
@@ -24,7 +25,7 @@ public object Agg_AVG__INT8__INT8 : Agg {
 
     override val signature: AggSignature = AggSignature(
         name = "avg",
-        returns = INT8,
+        returns = DECIMAL,
         parameters = listOf(
             FnParameter("value", INT8),
         ),
@@ -32,7 +33,7 @@ public object Agg_AVG__INT8__INT8 : Agg {
         isDecomposable = true
     )
 
-    override fun accumulator(): Agg.Accumulator = AccumulatorAvg(INT8)
+    override fun accumulator(): Agg.Accumulator = AccumulatorAvg(DECIMAL)
 }
 
 @OptIn(PartiQLValueExperimental::class, FnExperimental::class)
@@ -40,7 +41,7 @@ public object Agg_AVG__INT16__INT16 : Agg {
 
     override val signature: AggSignature = AggSignature(
         name = "avg",
-        returns = INT16,
+        returns = DECIMAL,
         parameters = listOf(
             FnParameter("value", INT16),
         ),
@@ -48,7 +49,7 @@ public object Agg_AVG__INT16__INT16 : Agg {
         isDecomposable = true
     )
 
-    override fun accumulator(): Agg.Accumulator = AccumulatorAvg(INT16)
+    override fun accumulator(): Agg.Accumulator = AccumulatorAvg(DECIMAL)
 }
 
 @OptIn(PartiQLValueExperimental::class, FnExperimental::class)
@@ -56,7 +57,7 @@ public object Agg_AVG__INT32__INT32 : Agg {
 
     override val signature: AggSignature = AggSignature(
         name = "avg",
-        returns = INT32,
+        returns = DECIMAL,
         parameters = listOf(
             FnParameter("value", INT32),
         ),
@@ -64,7 +65,7 @@ public object Agg_AVG__INT32__INT32 : Agg {
         isDecomposable = true
     )
 
-    override fun accumulator(): Agg.Accumulator = AccumulatorAvg(INT32)
+    override fun accumulator(): Agg.Accumulator = AccumulatorAvg(DECIMAL)
 }
 
 @OptIn(PartiQLValueExperimental::class, FnExperimental::class)
@@ -72,7 +73,7 @@ public object Agg_AVG__INT64__INT64 : Agg {
 
     override val signature: AggSignature = AggSignature(
         name = "avg",
-        returns = INT64,
+        returns = DECIMAL,
         parameters = listOf(
             FnParameter("value", INT64),
         ),
@@ -80,7 +81,7 @@ public object Agg_AVG__INT64__INT64 : Agg {
         isDecomposable = true
     )
 
-    override fun accumulator(): Agg.Accumulator = AccumulatorAvg(INT64)
+    override fun accumulator(): Agg.Accumulator = AccumulatorAvg(DECIMAL)
 }
 
 @OptIn(PartiQLValueExperimental::class, FnExperimental::class)
@@ -88,7 +89,7 @@ public object Agg_AVG__INT__INT : Agg {
 
     override val signature: AggSignature = AggSignature(
         name = "avg",
-        returns = INT,
+        returns = DECIMAL_ARBITRARY,
         parameters = listOf(
             FnParameter("value", INT),
         ),
@@ -96,7 +97,7 @@ public object Agg_AVG__INT__INT : Agg {
         isDecomposable = true
     )
 
-    override fun accumulator(): Agg.Accumulator = AccumulatorAvg(INT)
+    override fun accumulator(): Agg.Accumulator = AccumulatorAvg(DECIMAL_ARBITRARY)
 }
 
 @OptIn(PartiQLValueExperimental::class, FnExperimental::class)
@@ -152,7 +153,7 @@ public object Agg_AVG__ANY__ANY : Agg {
 
     override val signature: AggSignature = AggSignature(
         name = "avg",
-        returns = ANY,
+        returns = DECIMAL_ARBITRARY,
         parameters = listOf(
             FnParameter("value", ANY),
         ),
@@ -160,5 +161,5 @@ public object Agg_AVG__ANY__ANY : Agg {
         isDecomposable = true
     )
 
-    override fun accumulator(): Agg.Accumulator = AccumulatorAvg()
+    override fun accumulator(): Agg.Accumulator = AccumulatorAvg(DECIMAL_ARBITRARY)
 }