diff --git a/addons/account/models/chart_template.py b/addons/account/models/chart_template.py
index e3325b06755..f09a147308b 100644
--- a/addons/account/models/chart_template.py
+++ b/addons/account/models/chart_template.py
@@ -5,6 +5,7 @@ import csv
 from collections import defaultdict
 from functools import wraps
 from inspect import getmembers
+from copy import deepcopy
 
 import logging
 import re
@@ -495,7 +496,7 @@ class AccountChartTemplate(models.AbstractModel):
                 created_models.add(model)
 
         created_vals = {}
-        for model, data in defer(list(data.items())):
+        for model, data in defer(list(deepcopy(data).items())):
             create_vals = []
             for xml_id, record in data.items():
                 # Extract the translations from the values
diff --git a/addons/l10n_ar_withholding/__init__.py b/addons/l10n_ar_withholding/__init__.py
index cb742dc6a2e..170707ae9f4 100644
--- a/addons/l10n_ar_withholding/__init__.py
+++ b/addons/l10n_ar_withholding/__init__.py
@@ -12,7 +12,9 @@ _logger = logging.getLogger(__name__)
 def _l10n_ar_withholding_post_init(env):
     """ Existing companies that have the Argentinean Chart of Accounts set """
     template_codes = ['ar_ri', 'ar_ex', 'ar_base']
-    for template_code in template_codes:
+    ar_companies = env['res.company'].search([('chart_template', 'in', template_codes)])
+    used_template_codes = set(ar_companies.mapped('chart_template'))
+    for template_code in used_template_codes:
         data = {
             model: env['account.chart.template']._parse_csv(template_code, model, module='l10n_ar_withholding')
             for model in [
@@ -21,12 +23,11 @@ def _l10n_ar_withholding_post_init(env):
                 'account.tax',
             ]
         }
-        for company in env['res.company'].search([('chart_template', '=', template_code)]):
+        for company in ar_companies.filtered(lambda c: c.chart_template == template_code):
             _logger.info("Company %s already has the Argentinean localization installed, updating...", company.name)
             company_chart_template = env['account.chart.template'].with_company(company)
-            company_data = dict(data)
-            company_chart_template._deref_account_tags(template_code, company_data['account.tax'])
-            company_chart_template._load_data(company_data)
+            company_chart_template._deref_account_tags(template_code, data['account.tax'])
+            company_chart_template._load_data(data)
             company.l10n_ar_tax_base_account_id = env.ref('account.%i_base_tax_account' % company.id)
 
             if env.ref('base.module_l10n_ar_withholding').demo: