diff --git a/htdocs/admin/facture.php b/htdocs/admin/facture.php
index 568cd5dca21..e136d8663fe 100644
--- a/htdocs/admin/facture.php
+++ b/htdocs/admin/facture.php
@@ -280,6 +280,24 @@ if ($action == 'set_FAC_AUTO_FILLJS')
 	}
 }
 
+if ($action == 'set_INVOICE_CREDIT_NOTE_STANDALONE')
+{
+	$freetext = GETPOST('INVOICE_CREDIT_NOTE_STANDALONE');	// No alpha here, we want exact string
+
+	$res = dolibarr_set_const($db, "INVOICE_CREDIT_NOTE_STANDALONE",$freetext,'chaine',0,'',$conf->entity);
+
+	if (! $res > 0) $error++;
+
+	if (! $error)
+	{
+		setEventMessage($langs->trans("SetupSaved"));
+	}
+	else
+	{
+		setEventMessage($langs->trans("Error"),'errors');
+	}
+}
+
 
 /*
  * View
@@ -750,6 +768,34 @@ print '<input type="submit" class="button" value="'.$langs->trans("Modify").'" /
 print "</td></tr>\n";
 print '</form>';
 
+// Add js auto fill amount on paiement form
+$var=! $var;
+print '<form action="'.$_SERVER["PHP_SELF"].'" method="POST">';
+print '<input type="hidden" name="token" value="'.$_SESSION['newtoken'].'" />';
+print '<input type="hidden" name="action" value="set_FAC_AUTO_FILLJS" />';
+print '<tr '.$bc[$var].'><td>';
+print $langs->trans("JSOnPaimentBill");
+print '</td><td width="60" align="center">';
+print $form->selectyesno("FAC_AUTO_FILLJS",$conf->global->FAC_AUTO_FILLJS,1);
+print '</td><td align="right">';
+print '<input type="submit" class="button" value="'.$langs->trans("Modify").'" />';
+print "</td></tr>\n";
+print '</form>';
+
+// Allow to create credit note not related to an invoice
+$var=! $var;
+print '<form action="'.$_SERVER["PHP_SELF"].'" method="POST">';
+print '<input type="hidden" name="token" value="'.$_SESSION['newtoken'].'" />';
+print '<input type="hidden" name="action" value="set_INVOICE_CREDIT_NOTE_STANDALONE" />';
+print '<tr '.$bc[$var].'><td>';
+print $langs->trans("AllowCreditNoteWithoutRelatedInvoice");
+print '</td><td width="60" align="center">';
+print $form->selectyesno("INVOICE_CREDIT_NOTE_STANDALONE",$conf->global->INVOICE_CREDIT_NOTE_STANDALONE,1);
+print '</td><td align="right">';
+print '<input type="submit" class="button" value="'.$langs->trans("Modify").'" />';
+print "</td></tr>\n";
+print '</form>';
+
 $var=! $var;
 print '<form action="'.$_SERVER["PHP_SELF"].'" method="POST">';
 print '<input type="hidden" name="token" value="'.$_SESSION['newtoken'].'" />';
@@ -784,20 +830,6 @@ print '<input type="submit" class="button" value="'.$langs->trans("Modify").'" /
 print "</td></tr>\n";
 print '</form>';
 
-// Add js auto fill amount on paiement form
-$var=! $var;
-print '<form action="'.$_SERVER["PHP_SELF"].'" method="POST">';
-print '<input type="hidden" name="token" value="'.$_SESSION['newtoken'].'" />';
-print '<input type="hidden" name="action" value="set_FAC_AUTO_FILLJS" />';
-print '<tr '.$bc[$var].'><td>';
-print $langs->trans("JSOnPaimentBill");
-print '</td><td width="60" align="center">';
-print $form->selectyesno("FAC_AUTO_FILLJS",$conf->global->FAC_AUTO_FILLJS,1);
-print '</td><td align="right">';
-print '<input type="submit" class="button" value="'.$langs->trans("Modify").'" />';
-print "</td></tr>\n";
-print '</form>';
-
 print '</table>';
 
 
diff --git a/htdocs/compta/facture.php b/htdocs/compta/facture.php
index 983331bd412..47f8b21eb6a 100644
--- a/htdocs/compta/facture.php
+++ b/htdocs/compta/facture.php
@@ -713,7 +713,8 @@ if (empty($reshook))
 		// Credit note invoice
 		if ($_POST['type'] == Facture::TYPE_CREDIT_NOTE)
 		{
-			if (! ($_POST['fac_avoir'] > 0))
+			$sourceinvoice = GETPOST('fac_avoir');
+			if (! ($sourceinvoice > 0) && empty($conf->global->INVOICE_CREDIT_NOTE_STANDALONE))
 			{
 				$error ++;
 				setEventMessages($langs->trans("ErrorFieldRequired", $langs->transnoentitiesnoconv("CorrectInvoice")), null, 'errors');
@@ -746,7 +747,7 @@ if (empty($reshook))
 				$object->location_incoterms = GETPOST('location_incoterms', 'alpha');
 
 				// Proprietes particulieres a facture avoir
-				$object->fk_facture_source = $_POST['fac_avoir'];
+				$object->fk_facture_source = $sourceinvoice > 0 ? $sourceinvoice : '';
 				$object->type = Facture::TYPE_CREDIT_NOTE;
 
 				$id = $object->create($user);
@@ -2033,7 +2034,7 @@ if ($action == 'create')
 		$newinvoice_static->paye = $valarray ['paye'];
 
 		$optionsav .= '<option value="' . $key . '"';
-		if ($key == $_POST['fac_avoir'])
+		if ($key == GETPOST('fac_avoir'))
 			$optionsav .= ' selected';
 		$optionsav .= '>';
 		$optionsav .= $newinvoice_static->ref;
@@ -2831,7 +2832,7 @@ else if ($id > 0 || ! empty($ref))
 		$facreplaced->fetch($object->fk_facture_source);
 		print ' (' . $langs->transnoentities("ReplaceInvoice", $facreplaced->getNomUrl(1)) . ')';
 	}
-	if ($object->type == Facture::TYPE_CREDIT_NOTE) {
+	if ($object->type == Facture::TYPE_CREDIT_NOTE && !empty($object->fk_facture_source)) {
 		$facusing = new Facture($db);
 		$facusing->fetch($object->fk_facture_source);
 		print ' (' . $langs->transnoentities("CorrectInvoice", $facusing->getNomUrl(1)) . ')';
@@ -3685,6 +3686,15 @@ else if ($id > 0 || ! empty($ref))
 					print '<div class="inline-block divButAction"><a class="butAction" href="facture/fiche-rec.php?facid=' . $object->id . '&amp;action=create">' . $langs->trans("ChangeIntoRepeatableInvoice") . '</a></div>';
 				}
 			}
+			
+			// Create a credit note
+			if (($object->type == Facture::TYPE_STANDARD || $object->type == Facture::TYPE_DEPOSIT || $object->type == Facture::TYPE_PROFORMA) && $object->statut > 0 && $user->rights->facture->creer)
+			{
+				if (! $objectidnext)
+				{
+					print '<div class="inline-block divButAction"><a class="butAction" href="' . $_SERVER['PHP_SELF'] . '?socid=' . $object->socid .'&amp;fac_avoir=' . $object->id . '&amp;action=create&amp;type=2">' . $langs->trans("CreateCreditNote") . '</a></div>';
+				}
+			}
 
 			//Create next situation invoice
 			if ($user->rights->facture->creer && ($object->type == 5) && ($object->statut == 1 || $object->statut == 2)) {
diff --git a/htdocs/core/modules/facture/doc/pdf_crabe.modules.php b/htdocs/core/modules/facture/doc/pdf_crabe.modules.php
index a0514c001e9..e552f3ba9ed 100644
--- a/htdocs/core/modules/facture/doc/pdf_crabe.modules.php
+++ b/htdocs/core/modules/facture/doc/pdf_crabe.modules.php
@@ -1503,7 +1503,7 @@ class pdf_crabe extends ModelePDFFactures
 			$pdf->SetTextColor(0,0,60);
 			$pdf->MultiCell($w, 3, $outputlangs->transnoentities("ReplacementInvoice").' : '.$outputlangs->convToOutputCharset($objectreplaced->ref), '', 'R');
 		}
-		if ($object->type == 2)
+		if ($object->type == 2 && !empty($object->fk_facture_source))
 		{
 			$objectreplaced=new Facture($this->db);
 			$objectreplaced->fetch($object->fk_facture_source);
diff --git a/htdocs/langs/en_US/admin.lang b/htdocs/langs/en_US/admin.lang
index 9bf9233f76b..f53e11c95e5 100755
--- a/htdocs/langs/en_US/admin.lang
+++ b/htdocs/langs/en_US/admin.lang
@@ -1177,6 +1177,7 @@ CreditNotePDFModules=Credit note document models
 CreditNote=Credit note
 CreditNotes=Credit notes
 ForceInvoiceDate=Force invoice date to validation date
+AllowCreditNoteWithoutRelatedInvoice=Allow to create credit note without a related invoice
 DisableRepeatable=Disable repeatable invoices
 SuggestedPaymentModesIfNotDefinedInInvoice=Suggested payments mode on invoice by default if not defined for invoice
 EnableEditDeleteValidInvoice=Enable the possibility to edit/delete valid invoice with no payment
diff --git a/htdocs/langs/en_US/bills.lang b/htdocs/langs/en_US/bills.lang
index 94e1fa60251..b97836c028e 100644
--- a/htdocs/langs/en_US/bills.lang
+++ b/htdocs/langs/en_US/bills.lang
@@ -88,6 +88,7 @@ ClassifyCanceled=Classify 'Abandoned'
 ClassifyClosed=Classify 'Closed'
 ClassifyUnBilled=Classify 'Unbilled'
 CreateBill=Create Invoice
+CreateCreditNote=Create credit note
 AddBill=Create invoice or credit note
 AddToDraftInvoices=Add to draft invoice
 DeleteBill=Delete invoice