diff --git a/lib/dialects/mssql/query.js b/lib/dialects/mssql/query.js
index b14c80391591..35e9a02847bc 100644
--- a/lib/dialects/mssql/query.js
+++ b/lib/dialects/mssql/query.js
@@ -9,6 +9,13 @@ const { logger } = require('../../utils/logger');
 
 const debug = logger.debugContext('sql:mssql');
 
+function getScale(aNum) {
+  if (!Number.isFinite(aNum)) return 0;
+  let e = 1;
+  while (Math.round(aNum * e) / e !== aNum) e *= 10;
+  return Math.log10(e);
+}
+
 class Query extends AbstractQuery {
   getInsertIdField() {
     return 'id';
@@ -27,7 +34,7 @@ class Query extends AbstractQuery {
       } else {
         paramType.type = TYPES.Numeric;
         //Default to a reasonable numeric precision/scale pending more sophisticated logic
-        paramType.typeOptions = { precision: 30, scale: 15 };
+        paramType.typeOptions = { precision: 30, scale: getScale(value) };
       }
     }
     if (Buffer.isBuffer(value)) {
diff --git a/test/unit/dialects/mssql/query.test.js b/test/unit/dialects/mssql/query.test.js
index ef151977fb05..90ef90479155 100644
--- a/test/unit/dialects/mssql/query.test.js
+++ b/test/unit/dialects/mssql/query.test.js
@@ -15,18 +15,22 @@ let sandbox, query;
 
 if (dialect === 'mssql') {
   describe('[MSSQL Specific] Query', () => {
-    describe('beginTransaction', () => {
-      beforeEach(() => {
-        sandbox = sinon.createSandbox();
-        const options = {
-          transaction: { name: 'transactionName' },
-          isolationLevel: 'REPEATABLE_READ',
-          logging: false
-        };
-        sandbox.stub(connectionStub, 'beginTransaction').callsArg(0);
-        query = new Query(connectionStub, sequelize, options);
-      });
+    beforeEach(() => {
+      sandbox = sinon.createSandbox();
+      const options = {
+        transaction: { name: 'transactionName' },
+        isolationLevel: 'REPEATABLE_READ',
+        logging: false
+      };
+      sandbox.stub(connectionStub, 'beginTransaction').callsArg(0);
+      query = new Query(connectionStub, sequelize, options);
+    });
+
+    afterEach(() => {
+      sandbox.restore();
+    });
 
+    describe('beginTransaction', () => {
       it('should call beginTransaction with correct arguments', () => {
         return query._run(connectionStub, 'BEGIN TRANSACTION')
           .then(() => {
@@ -35,10 +39,6 @@ if (dialect === 'mssql') {
             expect(connectionStub.beginTransaction.args[0][2]).to.equal(tediousIsolationLevel.REPEATABLE_READ);
           });
       });
-
-      afterEach(() => {
-        sandbox.restore();
-      });
     });
 
     describe('formatBindParameters', () => {
@@ -64,5 +64,25 @@ if (dialect === 'mssql') {
         expect(result[0]).to.equal(expected);
       });
     });
+
+    describe('getSQLTypeFromJsType', () => {
+      const TYPES = tedious.TYPES;
+      it('should return correct parameter type', () => {
+        expect(query.getSQLTypeFromJsType(2147483647, TYPES)).to.eql({ type: TYPES.Int, typeOptions: {} });
+        expect(query.getSQLTypeFromJsType(-2147483648, TYPES)).to.eql({ type: TYPES.Int, typeOptions: {} });
+
+        expect(query.getSQLTypeFromJsType(2147483648, TYPES)).to.eql({ type: TYPES.BigInt, typeOptions: {} });
+        expect(query.getSQLTypeFromJsType(-2147483649, TYPES)).to.eql({ type: TYPES.BigInt, typeOptions: {} });
+
+        expect(query.getSQLTypeFromJsType(Buffer.from('abc'), TYPES)).to.eql({ type: TYPES.VarBinary, typeOptions: {} });
+      });
+
+      it('should return parameter type correct scale for float', () => {
+        expect(query.getSQLTypeFromJsType(1.23, TYPES)).to.eql({ type: TYPES.Numeric, typeOptions: { precision: 30, scale: 2 } });
+        expect(query.getSQLTypeFromJsType(0.30000000000000004, TYPES)).to.eql({ type: TYPES.Numeric, typeOptions: { precision: 30, scale: 17 } });
+        expect(query.getSQLTypeFromJsType(2.5e-15, TYPES)).to.eql({ type: TYPES.Numeric, typeOptions: { precision: 30, scale: 16 } });
+      });
+    });
+
   });
 }