diff --git a/l10n_us_hr_payroll/data/state/ok_oklahoma.xml b/l10n_us_hr_payroll/data/state/ok_oklahoma.xml
index 04aa8380..8968ea39 100644
--- a/l10n_us_hr_payroll/data/state/ok_oklahoma.xml
+++ b/l10n_us_hr_payroll/data/state/ok_oklahoma.xml
@@ -12,6 +12,12 @@
             <field name="rule_parameter_id" ref="rule_parameter_us_ok_suta_wage_base"/>
             <field name="date_from" eval="datetime(2020, 1, 1).date()"/>
         </record>
+        <!-- https://oklahoma.gov/content/dam/ok/en/omes/documents/car/newsletter/2021RatesAndMaximums.pdf -->
+        <record id="rule_parameter_us_ok_suta_wage_base_2021" model="hr.rule.parameter.value">
+            <field name="parameter_value">24000.0</field>
+            <field name="rule_parameter_id" ref="rule_parameter_us_ok_suta_wage_base"/>
+            <field name="date_from" eval="datetime(2021, 1, 1).date()"/>
+        </record>
     </data>
 
     <!-- Rate -->
@@ -26,7 +32,14 @@
             <field name="rule_parameter_id" ref="rule_parameter_us_ok_suta_rate"/>
             <field name="date_from" eval="datetime(2020, 1, 1).date()"/>
         </record>
+        <!-- https://oklahoma.gov/content/dam/ok/en/omes/documents/car/newsletter/2021RatesAndMaximums.pdf -->
+        <record id="rule_parameter_us_ok_suta_rate_2021" model="hr.rule.parameter.value">
+            <field name="parameter_value">1.0</field>
+            <field name="rule_parameter_id" ref="rule_parameter_us_ok_suta_rate"/>
+            <field name="date_from" eval="datetime(2021, 1, 1).date()"/>
+        </record>
     </data>
+
     <!-- table from https://www.ok.gov/tax/documents/2020WHTables.pdf -->
     <record id="rule_parameter_us_ok_sit_allowances_rate" model="hr.rule.parameter">
         <field name="name">US OK Oklahoma Allowances Rate</field>
@@ -34,6 +47,7 @@
         <field name="country_id" ref="base.us"/>
     </record>
     <data noupdate="1">
+        <!-- Unchanged in 2021 https://www.ok.gov/tax/documents/2021WHTables.pdf -->
         <record id="rule_parameter_us_ok_sit_allowances_rate_2020" model="hr.rule.parameter.value">
             <field name="parameter_value">{
                 'weekly' :        19.23,
@@ -48,13 +62,15 @@
             <field name="date_from" eval="datetime(2020, 1, 1).date()"/>
         </record>
     </data>
-    <!-- table from https://www.ok.gov/tax/documents/2020WHTables.pdf -->
+
     <record id="rule_parameter_us_ok_sit_tax_rate" model="hr.rule.parameter">
         <field name="name">US OK Oklahoma SIT Tax Rate</field>
         <field name="code">us_ok_sit_tax_rate</field>
         <field name="country_id" ref="base.us"/>
     </record>
     <data noupdate="1">
+        <!-- table from https://www.ok.gov/tax/documents/2020WHTables.pdf -->
+        <!-- Unchanged in 2021 https://www.ok.gov/tax/documents/2021WHTables.pdf -->
         <record id="rule_parameter_us_ok_sit_tax_rate_2020" model="hr.rule.parameter.value">
             <field name="parameter_value">{
                 'single': {
diff --git a/l10n_us_hr_payroll/tests/test_us_ok_oklahoma_payslip_2021.py b/l10n_us_hr_payroll/tests/test_us_ok_oklahoma_payslip_2021.py
new file mode 100755
index 00000000..096f3dfd
--- /dev/null
+++ b/l10n_us_hr_payroll/tests/test_us_ok_oklahoma_payslip_2021.py
@@ -0,0 +1,38 @@
+# Part of Hibou Suite Professional. See LICENSE_PROFESSIONAL file for full copyright and licensing details.
+
+from datetime import date, timedelta
+from .common import TestUsPayslip
+
+
+class TestUsOKPayslip(TestUsPayslip):
+    ###
+    #   2021 Taxes and Rates
+    ###
+    OK_UNEMP_MAX_WAGE = 24000.0
+    OK_UNEMP = 1.0
+    # Calculation based on example https://www.ok.gov/tax/documents/2021WHTables.pdf
+
+    def _test_sit(self, wage, filing_status, allowances, additional_withholding, exempt, schedule_pay,  date_start, expected_withholding):
+        employee = self._createEmployee()
+        contract = self._createContract(employee,
+                                        wage=wage,
+                                        state_id=self.get_us_state('OK'),
+                                        ok_w4_sit_filing_status=filing_status,
+                                        ok_w4_sit_allowances=allowances,
+                                        state_income_tax_additional_withholding=additional_withholding,
+                                        state_income_tax_exempt=exempt,
+                                        schedule_pay=schedule_pay)
+        payslip = self._createPayslip(employee, date_start, date_start + timedelta(days=7))
+        payslip.compute_sheet()
+        cats = self._getCategories(payslip)
+
+        self._log('Computed period tax: ' + str(expected_withholding))
+        self.assertPayrollEqual(cats.get('EE_US_SIT', 0.0), -expected_withholding)
+
+    def test_2021_taxes_example(self):
+        self._test_er_suta('OK', self.OK_UNEMP, date(2021, 1, 1), wage_base=self.OK_UNEMP_MAX_WAGE)
+        self._test_sit(1825, 'married', 2, 0, False, 'semi-monthly', date(2021, 1, 1), 46.00)
+        self._test_sit(1825, 'married', 2, 0, True, 'monthly', date(2021, 1, 1), 0.00)
+        self._test_sit(1000, 'single', 1, 0, False, 'weekly', date(2021, 1, 1), 39.00)
+        self._test_sit(1000, 'single', 1, 10, False, 'weekly', date(2021, 1, 1), 49.00)
+        self._test_sit(5000, 'head_household', 2, 10, False, 'monthly', date(2021, 1, 1), 210.00)