diff --git a/src/constants.ts b/src/constants.ts
index a56b8031..1311ef06 100644
--- a/src/constants.ts
+++ b/src/constants.ts
@@ -1,5 +1,5 @@
 /** @internal */
-export const BSON_MAJOR_VERSION = 5 as const;
+export const BSON_MAJOR_VERSION = 6 as const;
 
 /** @internal */
 export const BSON_INT32_MAX = 0x7fffffff;
diff --git a/test/node/bson_type_classes.test.ts b/test/node/bson_type_classes.test.ts
index 3d7c3497..7b9b2105 100644
--- a/test/node/bson_type_classes.test.ts
+++ b/test/node/bson_type_classes.test.ts
@@ -80,8 +80,8 @@ describe('BSON Type classes common interfaces', () => {
           ));
       }
 
-      it(`defines a Symbol.for('@@mdb.bson.version') property equal to 5`, () =>
-        expect(TypeClass.prototype).to.have.property(Symbol.for('@@mdb.bson.version'), 5));
+      it(`defines a Symbol.for('@@mdb.bson.version') property equal to 6`, () =>
+        expect(TypeClass.prototype).to.have.property(Symbol.for('@@mdb.bson.version'), 6));
 
       it(`defines a static fromExtendedJSON() method`, () =>
         expect(TypeClass).to.have.property('fromExtendedJSON').that.is.a('function'));
diff --git a/test/node/constants.test.ts b/test/node/constants.test.ts
index 03ef21d2..77d17e94 100644
--- a/test/node/constants.test.ts
+++ b/test/node/constants.test.ts
@@ -3,6 +3,12 @@ import { Binary } from '../register-bson';
 import * as constants from '../../src/constants';
 
 describe('BSON Constants', () => {
+  describe('.BSON_MAJOR_VERSION', () => {
+    it('returns the current major version', () => {
+      expect(constants.BSON_MAJOR_VERSION).to.equal(6);
+    });
+  });
+
   context('Binary Subtype', () => {
     /*
      subtype	::=
diff --git a/test/node/parser/serializer.test.ts b/test/node/parser/serializer.test.ts
index d09c11b1..c06161cc 100644
--- a/test/node/parser/serializer.test.ts
+++ b/test/node/parser/serializer.test.ts
@@ -47,7 +47,7 @@ describe('serialize()', () => {
       // a nested invalid _bsontype throws something different
       expect(() =>
         BSON.serialize({
-          a: { _bsontype: 'iLoveJavascript', [Symbol.for('@@mdb.bson.version')]: 5 }
+          a: { _bsontype: 'iLoveJavascript', [Symbol.for('@@mdb.bson.version')]: 6 }
         })
       ).to.throw(/invalid _bsontype/);
     });