diff --git a/src/bulk-load.ts b/src/bulk-load.ts
index fe47e4fff..26ac25a1c 100644
--- a/src/bulk-load.ts
+++ b/src/bulk-load.ts
@@ -429,10 +429,13 @@ class BulkLoad extends EventEmitter {
       collation: this.collation
     };
 
-    if ((type.id & 0x30) === 0x20) {
-      if (column.length == null && type.resolveLength) {
-        column.length = type.resolveLength(column);
-      }
+    // Note: this is deliberately not keyed off the legacy variable-length
+    // type id bit pattern ((type.id & 0x30) === 0x20), as that pattern does
+    // not hold for type ids introduced in TDS 7.2 and later (e.g. XMLTYPE
+    // 0xF1 or VECTORTYPE 0xF5). A type has a length whenever it can resolve
+    // one, mirroring how precision and scale are resolved below.
+    if (column.length == null && type.resolveLength) {
+      column.length = type.resolveLength(column);
     }
 
     if (type.resolvePrecision && column.precision == null) {
diff --git a/src/rpcrequest-payload.ts b/src/rpcrequest-payload.ts
index d2d15e2ae..35e24b0fa 100644
--- a/src/rpcrequest-payload.ts
+++ b/src/rpcrequest-payload.ts
@@ -88,12 +88,15 @@ class RpcRequestPayload implements Iterable<Buffer> {
 
     const type = parameter.type;
 
-    if ((type.id & 0x30) === 0x20) {
-      if (parameter.length) {
-        param.length = parameter.length;
-      } else if (type.resolveLength) {
-        param.length = type.resolveLength(parameter);
-      }
+    // Note: this is deliberately not keyed off the legacy variable-length
+    // type id bit pattern ((type.id & 0x30) === 0x20), as that pattern does
+    // not hold for type ids introduced in TDS 7.2 and later (e.g. XMLTYPE
+    // 0xF1 or VECTORTYPE 0xF5). A type has a length whenever it can resolve
+    // one, mirroring how precision and scale are resolved below.
+    if (parameter.length) {
+      param.length = parameter.length;
+    } else if (type.resolveLength) {
+      param.length = type.resolveLength(parameter);
     }
 
     if (parameter.precision) {
diff --git a/test/unit/rpcrequest-payload-test.ts b/test/unit/rpcrequest-payload-test.ts
new file mode 100644
index 000000000..a4d7e7632
--- /dev/null
+++ b/test/unit/rpcrequest-payload-test.ts
@@ -0,0 +1,92 @@
+import { assert } from 'chai';
+
+import RpcRequestPayload from '../../src/rpcrequest-payload';
+import { typeByName as TYPES, type DataType, type Parameter, type ParameterData } from '../../src/data-type';
+import { type InternalConnectionOptions } from '../../src/connection';
+
+const options = { tdsVersion: '7_4' } as InternalConnectionOptions;
+const txnDescriptor = Buffer.from([0, 0, 0, 0, 0, 0, 0, 0]);
+
+describe('RpcRequestPayload', function() {
+  describe('parameter length resolution', function() {
+    // A stub type whose id does _not_ match the legacy variable-length type
+    // id bit pattern ((id & 0x30) === 0x20), like the type ids introduced
+    // in TDS 7.2 and later (e.g. XMLTYPE 0xF1 or VECTORTYPE 0xF5).
+    function buildModernIdType(receivedLengths: (number | undefined)[]): DataType {
+      return {
+        id: 0xF5,
+        type: 'STUB',
+        name: 'Stub',
+
+        declaration() {
+          return 'stub';
+        },
+
+        resolveLength(parameter: Parameter) {
+          return (parameter.value as { length: number }).length;
+        },
+
+        generateTypeInfo(parameter: ParameterData) {
+          receivedLengths.push(parameter.length);
+          return Buffer.from([this.id]);
+        },
+
+        generateParameterLength(parameter: ParameterData) {
+          receivedLengths.push(parameter.length);
+          return Buffer.alloc(0);
+        },
+
+        * generateParameterData(parameter: ParameterData) {
+          receivedLengths.push(parameter.length);
+        },
+
+        validate(value) {
+          return value;
+        }
+      };
+    }
+
+    it('resolves the length for types with ids outside the legacy variable-length id bit pattern', function() {
+      const receivedLengths: (number | undefined)[] = [];
+      const parameter: Parameter = {
+        type: buildModernIdType(receivedLengths),
+        name: 'value',
+        value: { length: 3 },
+        output: false
+      };
+
+      assert.isNotEmpty([...new RpcRequestPayload('proc', [parameter], txnDescriptor, options, undefined)]);
+      assert.deepEqual(receivedLengths, [3, 3, 3]);
+    });
+
+    it('prefers an explicitly specified length', function() {
+      const receivedLengths: (number | undefined)[] = [];
+      const parameter: Parameter = {
+        type: buildModernIdType(receivedLengths),
+        name: 'value',
+        value: { length: 3 },
+        length: 42,
+        output: false
+      };
+
+      assert.isNotEmpty([...new RpcRequestPayload('proc', [parameter], txnDescriptor, options, undefined)]);
+      assert.deepEqual(receivedLengths, [42, 42, 42]);
+    });
+
+    it('keeps resolving the length for legacy variable-length type ids', function() {
+      const parameter: Parameter = {
+        type: TYPES.VarBinary,
+        name: 'value',
+        value: Buffer.from([1, 2, 3]),
+        output: false
+      };
+
+      const data = Buffer.concat([...new RpcRequestPayload('proc', [parameter], txnDescriptor, options, undefined)]);
+
+      // TYPE_INFO for a varbinary(3) parameter: BIGVARBINARYTYPE with a
+      // maximum length of 3 bytes, followed by the 3 byte value.
+      const typeInfo = Buffer.from([0xA5, 0x03, 0x00]);
+      assert.notStrictEqual(data.indexOf(typeInfo), -1);
+    });
+  });
+});