diff --git a/internal/models/monthlyReport.go b/internal/models/monthlyReport.go
index c7cb11237831526f0946e38f275c3439390d550d..53273487ee833efd8462ab5e321d5eb17971ad05 100644
--- a/internal/models/monthlyReport.go
+++ b/internal/models/monthlyReport.go
@@ -87,7 +87,7 @@ func (dh *DataHandler) getMonthlyReport(year int, month int) (monthlyReport Mont
 	err = dh.sqlClient.Where("year = ? AND month = ?", year, month).First(&mailSubject).Error
 	if err != nil || mailSubject.Subject == "" {
 		// Build default object
-		mailSubject.Subject = fmt.Sprintf("[Ecolyo] Votre bilan %s %v", getMonthNameWithPrep(month-1), year)
+		mailSubject.Subject = fmt.Sprintf("[Ecolyo] Votre bilan %s", getDateWithPrep(month-1, year))
 	}
 
 	var monthlyNews MonthlyNews
@@ -111,7 +111,7 @@ func (dh *DataHandler) getMonthlyReport(year int, month int) (monthlyReport Mont
 	return monthlyReport, nil
 }
 
-func getMonthNameWithPrep(month int) string {
+func getDateWithPrep(month int, year int) string {
 	frenchMonths := []string{
 		"de janvier",
 		"de février",
@@ -126,5 +126,14 @@ func getMonthNameWithPrep(month int) string {
 		"de novembre",
 		"de décembre",
 	}
-	return frenchMonths[month]
+
+	var prevMonth = month - 1
+	var prevYear = year
+	// If month is January return December of the previous year
+	if month == 0 {
+		prevMonth = 11
+		prevYear = year - 1
+	}
+
+	return fmt.Sprintf("%s %d", frenchMonths[prevMonth], prevYear)
 }
diff --git a/internal/rootmux/rootmux_test.go b/internal/rootmux/rootmux_test.go
index 07f4b332f99fd15612dddf324838da3a270eea74..21e05c53e5c1a8a890784e998e1caca1f6f5562b 100644
--- a/internal/rootmux/rootmux_test.go
+++ b/internal/rootmux/rootmux_test.go
@@ -123,7 +123,7 @@ func unloggedTests(t *testing.T) {
 	// Try to get a monthlyReport (must fail because no parameters are given)
 	do("GET", "/api/common/monthlyReport", noH, "", http.StatusBadRequest, "")
 	// Try to get a monthlyReport (must pass empty)
-	do("GET", "/api/common/monthlyReport?year=2021&month=12", noH, "", http.StatusOK, `{"year":2021,"month":12,"subject":"[Ecolyo] Votre bilan de décembre 2021","info":"","image":"","newsTitle":"","newsContent":"","question":"","link":""}`)
+	do("GET", "/api/common/monthlyReport?year=2021&month=12", noH, "", http.StatusOK, `{"year":2021,"month":12,"subject":"[Ecolyo] Votre bilan de novembre 2021","info":"","image":"","newsTitle":"","newsContent":"","question":"","link":""}`)
 	// Try to get partnersInfo (must pass)
 	do("GET", "/api/common/partnersInfo", noH, "", http.StatusOK, `{"ID":1,"grdf_failure":false,"enedis_failure":false,"egl_failure":false,"notification_activated":false}`)
 }
@@ -156,7 +156,7 @@ func adminTests(t *testing.T) {
 		// Try to get the monthlyNews created (must pass)
 		do("GET", "/api/admin/monthlyNews/2021/1", xsrfHeader, "", http.StatusOK, `{"year":2021,"month":1,"title":"Les nouveautés du service","content":"Nouvelles fonctionnalités"`)
 		// Try to get the monthlyReport (must pass)
-		do("GET", "/api/common/monthlyReport/2021/1", noH, "", http.StatusOK, `{"year":2021,"month":1,"subject":"[Ecolyo] Votre bilan de janvier 2021","info":"","image":"","newsTitle":"Les nouveautés du service","newsContent":"Nouvelles fonctionnalités","question":"","link":""}`)
+		do("GET", "/api/common/monthlyReport/2021/1", noH, "", http.StatusOK, `{"year":2021,"month":1,"subject":"[Ecolyo] Votre bilan de décembre 2020","info":"","image":"","newsTitle":"Les nouveautés du service","newsContent":"Nouvelles fonctionnalités","question":"","link":""}`)
 
 		// Try to create a poll without the XSRF-TOKEN (must fail)
 		do("PUT", "/api/admin/poll", noH, newPollStr, http.StatusUnauthorized, "XSRF protection triggered")
@@ -171,7 +171,7 @@ func adminTests(t *testing.T) {
 		// Try to get the poll created (must pass)
 		do("GET", "/api/admin/poll/2021/1", xsrfHeader, "", http.StatusOK, newPollStr)
 		// Try to get the monthlyReport (must pass)
-		do("GET", "/api/common/monthlyReport/2021/1", noH, "", http.StatusOK, `{"year":2021,"month":1,"subject":"[Ecolyo] Votre bilan de janvier 2021","info":"","image":"","newsTitle":"Les nouveautés du service","newsContent":"Nouvelles fonctionnalités","question":"pollQuestion","link":"pollLink"}`)
+		do("GET", "/api/common/monthlyReport/2021/1", noH, "", http.StatusOK, `{"year":2021,"month":1,"subject":"[Ecolyo] Votre bilan de décembre 2020","info":"","image":"","newsTitle":"Les nouveautés du service","newsContent":"Nouvelles fonctionnalités","question":"pollQuestion","link":"pollLink"}`)
 
 		// Try to create a monthlyInfo without the XSRF-TOKEN (must fail)
 		do("PUT", "/api/admin/monthlyInfo", noH, monthlyInfoStr, http.StatusUnauthorized, "XSRF protection triggered")
@@ -186,7 +186,7 @@ func adminTests(t *testing.T) {
 		// Try to get the monthlyInfo created (must pass)
 		do("GET", "/api/admin/monthlyInfo/2021/1", xsrfHeader, "", http.StatusOK, monthlyInfoStr)
 		// Try to get the monthlyReport (must pass)
-		do("GET", "/api/common/monthlyReport/2021/1", noH, "", http.StatusOK, `{"year":2021,"month":1,"subject":"[Ecolyo] Votre bilan de janvier 2021","info":"Informations du mois","image":"imagebase64","newsTitle":"Les nouveautés du service","newsContent":"Nouvelles fonctionnalités","question":"pollQuestion","link":"pollLink"`)
+		do("GET", "/api/common/monthlyReport/2021/1", noH, "", http.StatusOK, `{"year":2021,"month":1,"subject":"[Ecolyo] Votre bilan de décembre 2020","info":"Informations du mois","image":"imagebase64","newsTitle":"Les nouveautés du service","newsContent":"Nouvelles fonctionnalités","question":"pollQuestion","link":"pollLink"`)
 
 		// Try to update the partnersInfo (must pass)
 		do("PUT", "/api/admin/partnersInfo", xsrfHeader, partnersInfoStr, http.StatusOK, partnersInfoStr)
@@ -219,7 +219,7 @@ func adminTests(t *testing.T) {
 		// Try to get a mail subject after it is deleted (must fail because not found)
 		do("GET", "/api/admin/mailSubject/2021/1", xsrfHeader, "", http.StatusNotFound, "")
 		// Try to get the monthlyReport (must pass)
-		do("GET", "/api/common/monthlyReport/2021/1", noH, "", http.StatusOK, `{"year":2021,"month":1,"subject":"[Ecolyo] Votre bilan de janvier 2021","info":"Informations du mois","image":"imagebase64","newsTitle":"","newsContent":"","question":"","link":""`)
+		do("GET", "/api/common/monthlyReport/2021/1", noH, "", http.StatusOK, `{"year":2021,"month":1,"subject":"[Ecolyo] Votre bilan de décembre 2020","info":"Informations du mois","image":"imagebase64","newsTitle":"","newsContent":"","question":"","link":""`)
 
 	}
 	// Try to login (must pass)