diff --git a/installer/data/mysql/atomicupdate/bug_33766-a11y_fix_ambiguous_form-field_in_opac-auth.tt b/installer/data/mysql/atomicupdate/bug_33766-a11y_fix_ambiguous_form-field_in_opac-auth.tt
new file mode 100755
index 0000000000..3bb5322875
--- /dev/null
+++ b/installer/data/mysql/atomicupdate/bug_33766-a11y_fix_ambiguous_form-field_in_opac-auth.tt
@@ -0,0 +1,18 @@
+use Modern::Perl;
+
+return {
+    bug_number  => "33766",
+    description => "Add syspref to determine text content of userid input field's label.",
+    up          => sub {
+        my ($args) = @_;
+        my ( $dbh, $out ) = @$args{qw(dbh out)};
+
+        # Do you stuffs here
+        $dbh->do(
+            q{INSERT IGNORE INTO systempreferences (variable,value) VALUES ('OPACLoginLabelTextContent','Cardnumber')  }
+        );
+
+        # sysprefs
+        say $out "Added new system preference 'OPACLoginLabelTextContent'";
+    },
+};
diff --git a/installer/data/mysql/mandatory/sysprefs.sql b/installer/data/mysql/mandatory/sysprefs.sql
index 7f5aad3553..0913272f5a 100644
--- a/installer/data/mysql/mandatory/sysprefs.sql
+++ b/installer/data/mysql/mandatory/sysprefs.sql
@@ -513,6 +513,7 @@ INSERT INTO systempreferences ( `variable`, `value`, `options`, `explanation`, `
 ('OPACLocalCoverImages','0','1','Display local cover images on OPAC search and details pages.','YesNo'),
 ('OpacLocationBranchToDisplay','holding','holding|home|both','In the OPAC, under location show which branch for Location in the record details.','Choice'),
 ('OpacLocationOnDetail','holding','holding|home|both|column','In the OPAC detail, display the shelving location on its own column or under a library columns.',  'Choice'),
+('OPACLoginLabelTextContent','Cardnumber',NULL,NULL,NULL),
 ('OpacMaintenance','0','','If ON, enables maintenance warning in OPAC','YesNo'),
 ('OPACMandatoryHoldDates', '', '|start|end|both', 'Define which hold dates are required on OPAC reserve form', 'Choice'),
 ('OpacMaxItemsToDisplay','50','','Max items to display at the OPAC on a biblio detail','Integer'),
diff --git a/koha-tmpl/intranet-tmpl/prog/en/modules/admin/preferences/opac.pref b/koha-tmpl/intranet-tmpl/prog/en/modules/admin/preferences/opac.pref
index ef816bf671..9bcaf0894b 100644
--- a/koha-tmpl/intranet-tmpl/prog/en/modules/admin/preferences/opac.pref
+++ b/koha-tmpl/intranet-tmpl/prog/en/modules/admin/preferences/opac.pref
@@ -181,6 +181,15 @@ OPAC:
                   column: "on a separate column"
             - "for items on the OPAC record details page."
             - "<br />Note: If 'on a separate column' is selected, you still need to enable the item_shelving_location display on the <a href='/cgi-bin/koha/admin/columns_settings.pl'>configure columns</a> administration page."
+        -
+            - Use
+            - pref: OPACLoginLabelTextContent
+              default: Cardnumber
+              choices:
+                  Cardnumber: Cardnumber
+                  Username: Username
+                  "Cardnumber or Username": Cardnumber or Username
+            - "as the text content of the userid input field's label."
         -
             - pref: OPACShowMusicalInscripts
               default: 0
@@ -533,6 +542,7 @@ OPAC:
               type: textarea
               syntax: text/html
               class: code
+
         -
             - pref: OpacBrowseSearch
               default: 0
diff --git a/koha-tmpl/opac-tmpl/bootstrap/en/includes/masthead.inc b/koha-tmpl/opac-tmpl/bootstrap/en/includes/masthead.inc
index e284d1ec9b..201a1411b9 100644
--- a/koha-tmpl/opac-tmpl/bootstrap/en/includes/masthead.inc
+++ b/koha-tmpl/opac-tmpl/bootstrap/en/includes/masthead.inc
@@ -438,7 +438,7 @@
                             <input type="hidden" name="koha_login_context" value="opac" />
                             <fieldset class="brief">
                                 <div class="local-login">
-                                    <label for="muserid">Login:</label><input type="text" id="muserid" name="login_userid" autocomplete="off" />
+                                    <label for="muserid">[% Koha.Preference('OPACLoginLabelTextContent') | html %]:</label><input type="text" id="muserid" name="login_userid" autocomplete="off" />
                                     <label for="mpassword">Password:</label><input type="password" id="mpassword" name="login_password" autocomplete="off" />
                                     <fieldset class="action">
                                         <input type="hidden" name="op" value="cud-login" />
diff --git a/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-auth.tt b/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-auth.tt
index bd87cc3cb0..a8cc5fdc34 100644
--- a/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-auth.tt
+++ b/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-auth.tt
@@ -242,7 +242,7 @@
                                             <input type="hidden" name="[% INPUT.name | html %]" value="[% INPUT.value | html %]" />
                                         [% END %]
                                         <div class="form-group">
-                                            <label for="userid">Login:</label>
+                                            <label for="userid">[% Koha.Preference('OPACLoginLabelTextContent') | html %]:</label>
                                             <input class="form-control" type="text"  size="25" id="userid"  name="login_userid" autocomplete="off" />
                                         </div>
                                         <div class="form-group">
diff --git a/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-main.tt b/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-main.tt
index 211e1e1419..762e74ac8e 100644
--- a/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-main.tt
+++ b/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-main.tt
@@ -200,7 +200,7 @@
                                             <p>If you do not have an external account, but do have a local account, you can still log in: </p>
                                         [% END # /IF  identity_providers.size %]
                                         <div class="local-login">
-                                            <label for="userid">Login:</label>
+                                            <label for="userid">[% Koha.Preference('OPACLoginLabelTextContent') | html %]:</label>
                                             <input class="form-control" type="text" id="userid" name="login_userid" autocomplete="off" />
                                             <label for="password">Password:</label>
                                             <input class="form-control" type="password" id="password" name="login_password" autocomplete="off" />
diff --git a/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-password-recovery.tt b/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-password-recovery.tt
index 1fefb27964..f3c5ef3ebe 100644
--- a/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-password-recovery.tt
+++ b/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-password-recovery.tt
@@ -132,7 +132,7 @@
                             <p>To reset your password, enter your login or your email address.</p>
                             <fieldset class="brief">
                                 <div class="form-group">
-                                    <label for="username">Login:</label>
+                                    <label for="username">[% Koha.Preference('OPACLoginLabelTextContent') | html %]:</label>
                                     <input class="form-control" type="text" id="username" size="40" name="username" value="[% username | html %]" />
                                 </div>
 
diff --git a/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-registration-confirmation.tt b/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-registration-confirmation.tt
index 6fef58e72a..09ccc99bfd 100644
--- a/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-registration-confirmation.tt
+++ b/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-registration-confirmation.tt
@@ -109,7 +109,7 @@
                                     <input type="hidden" name="op" value="cud-login">
                                     <fieldset class="brief">
                                         <legend>Log in to your account:</legend>
-                                        <label for="userid">Login:</label>
+                                        <label for="userid">[% Koha.Preference('OPACLoginLabelTextContent') | html %]:</label>
                                         [% IF Koha.Preference('PatronSelfRegistrationPrefillForm') %]
                                             <input class="form-control" type="text" id="userid" size="10" name="login_userid" value="[% borrower.userid | html %]" autocomplete="off" />
                                         [% ELSE %]
diff --git a/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-reset-password.tt b/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-reset-password.tt
index c433c72cdb..4abd96b6f1 100644
--- a/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-reset-password.tt
+++ b/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-reset-password.tt
@@ -75,7 +75,7 @@
 
                             <fieldset class="brief">
                                 <div class="form-group">
-                                    <label for="userid">Login:</label>
+                                    <label for="userid">[% Koha.Preference('OPACLoginLabelTextContent') | html %]:</label>
                                     <input class="form-control" autocomplete="off" type="text"  size="25" id="userid"  name="userid" />
                                 </div>
                                 <div class="form-group">
diff --git a/koha-tmpl/opac-tmpl/bootstrap/en/modules/sco/sco-main.tt b/koha-tmpl/opac-tmpl/bootstrap/en/modules/sco/sco-main.tt
index c57c2cadff..df6280ffe2 100644
--- a/koha-tmpl/opac-tmpl/bootstrap/en/modules/sco/sco-main.tt
+++ b/koha-tmpl/opac-tmpl/bootstrap/en/modules/sco/sco-main.tt
@@ -466,7 +466,7 @@
                                     <fieldset>
                                         [% IF ( Koha.Preference('SelfCheckoutByLogin') ) %]
                                             <legend>Log in to your account</legend>
-                                            <label for="patronlogin">Login:</label>
+                                            <label for="patronlogin">[% Koha.Preference('OPACLoginLabelTextContent') | html %]:</label>
                                             <input type="text" id="patronlogin" class="focus noEnterSubmit" size="20" name="patronlogin" autocomplete="off"/>
                                             <label for="patronpw">Password:</label>
                                             <input type="password" id="patronpw" size="20" name="patronpw" autocomplete="off"/>