diff --git a/checker/cost.go b/checker/cost.go
index 1b325eac..b9cd8a2e 100644
--- a/checker/cost.go
+++ b/checker/cost.go
@@ -930,6 +930,14 @@ func (c *coster) computeSize(e ast.Expr) *SizeEstimate {
 	if size, ok := c.computedSizes[e.ID()]; ok {
 		return &size
 	}
+	// Ensure size estimates are computed first as users may choose to override the costs that
+	// CEL would otherwise ascribe to the type.
+	node := astNode{expr: e, path: c.getPath(e), t: c.getType(e)}
+	if size := c.estimator.EstimateSize(node); size != nil {
+		// storing the computed size should reduce calls to EstimateSize()
+		c.computedSizes[e.ID()] = *size
+		return size
+	}
 	if size := computeExprSize(e); size != nil {
 		return size
 	}
@@ -942,12 +950,6 @@ func (c *coster) computeSize(e ast.Expr) *SizeEstimate {
 			return v.size
 		}
 	}
-	node := astNode{expr: e, path: c.getPath(e), t: c.getType(e)}
-	if size := c.estimator.EstimateSize(node); size != nil {
-		// storing the computed size should reduce calls to EstimateSize()
-		c.computedSizes[e.ID()] = *size
-		return size
-	}
 	return nil
 }
 
@@ -1014,8 +1016,7 @@ func computeTypeSize(t *types.Type) *SizeEstimate {
 // in addition to protobuf.Any and protobuf.Value (their size is not knowable at compile time).
 func isScalar(t *types.Type) bool {
 	switch t.Kind() {
-	case types.BoolKind, types.DoubleKind, types.DurationKind, types.IntKind,
-		types.NullTypeKind, types.TimestampKind, types.TypeKind, types.UintKind:
+	case types.BoolKind, types.DoubleKind, types.DurationKind, types.IntKind, types.TimestampKind, types.UintKind:
 		return true
 	case types.OpaqueKind:
 		if t.TypeName() == "optional_type" {
diff --git a/checker/cost_test.go b/checker/cost_test.go
index fb74cdf2..2bec0e94 100644
--- a/checker/cost_test.go
+++ b/checker/cost_test.go
@@ -628,6 +628,93 @@ func TestCost(t *testing.T) {
 			expr:   `['hello', 'hi'][0] != ['hello', 'bye'][1]`,
 			wanted: CostEstimate{Min: 23, Max: 23},
 		},
+		{
+			name:   "type call",
+			expr:   `type(1)`,
+			wanted: CostEstimate{Min: 1, Max: 1},
+		},
+		{
+			name: "type call variable",
+			expr: `type(self.val1)`,
+			vars: []*decls.VariableDecl{
+				decls.NewVariable("self", types.NewMapType(types.StringType, types.IntType)),
+			},
+			wanted: CostEstimate{Min: 3, Max: 3},
+		},
+		{
+			name: "type call variable equality",
+			expr: `type(self.val1) == int`,
+			vars: []*decls.VariableDecl{
+				decls.NewVariable("self", types.NewMapType(types.StringType, types.IntType)),
+			},
+			wanted: CostEstimate{Min: 5, Max: 1844674407370955268},
+		},
+		{
+			name:   "type literal equality cost",
+			expr:   `type(1) == int`,
+			wanted: CostEstimate{Min: 3, Max: 1844674407370955266},
+		},
+		{
+			name:   "type variable equality cost",
+			expr:   `type(1) == int`,
+			wanted: CostEstimate{Min: 3, Max: 1844674407370955266},
+		},
+		{
+			name: "namespace variable equality",
+			expr: `self.val1 == 1.0`,
+			vars: []*decls.VariableDecl{
+				decls.NewVariable("self.val1", types.DoubleType),
+			},
+			wanted: CostEstimate{Min: 2, Max: 2},
+		},
+		{
+			name: "simple map variable equality",
+			expr: `self.val1 == 1.0`,
+			vars: []*decls.VariableDecl{
+				decls.NewVariable("self", types.NewMapType(types.StringType, types.DoubleType)),
+			},
+			wanted: CostEstimate{Min: 3, Max: 3},
+		},
+		{
+			name: "date-time math",
+			vars: []*decls.VariableDecl{
+				decls.NewVariable("self", types.NewMapType(types.StringType, types.TimestampType)),
+			},
+			expr:   `self.val1 == timestamp('2011-08-18T00:00:00.000+01:00') + duration('19h3m37s10ms')`,
+			wanted: FixedCostEstimate(6),
+		},
+		{
+			name: "date-time math self-conversion",
+			vars: []*decls.VariableDecl{
+				decls.NewVariable("self", types.NewMapType(types.StringType, types.TimestampType)),
+			},
+			expr:   `timestamp(self.val1) == timestamp('2011-08-18T00:00:00.000+01:00') + duration('19h3m37s10ms')`,
+			wanted: FixedCostEstimate(7),
+		},
+		{
+			name: "boolean vars equal",
+			vars: []*decls.VariableDecl{
+				decls.NewVariable("self", types.NewMapType(types.StringType, types.BoolType)),
+			},
+			expr:   `self.val1 != self.val2`,
+			wanted: FixedCostEstimate(5),
+		},
+		{
+			name: "boolean var equals literal",
+			vars: []*decls.VariableDecl{
+				decls.NewVariable("self", types.NewMapType(types.StringType, types.BoolType)),
+			},
+			expr:   `self.val1 != true`,
+			wanted: FixedCostEstimate(3),
+		},
+		{
+			name: "double var equals literal",
+			vars: []*decls.VariableDecl{
+				decls.NewVariable("self", types.NewMapType(types.StringType, types.DoubleType)),
+			},
+			expr:   `self.val1 == 1.0`,
+			wanted: FixedCostEstimate(3),
+		},
 	}
 
 	for _, tst := range cases {