diff --git a/CHANGELOG.fr.md b/CHANGELOG.fr.md
index a3d909f..5daf118 100644
--- a/CHANGELOG.fr.md
+++ b/CHANGELOG.fr.md
@@ -2,6 +2,10 @@
 
 ## [Non publié]
 
+### Modifié
+- Rapport Catégorie dans le temps : suppression du filtre codé en dur sur les dépenses, affiche maintenant tous les types de transactions par défaut (#41)
+- Rapport Catégorie dans le temps : ajout d'un filtre par type (dépense/revenu/transfert) dans le panneau de filtre à droite (#41)
+
 ## [0.6.6]
 
 ### Modifié
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8c15ed6..f764f12 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Changed
+- Category Over Time report: removed hard-coded expense-only filter, now shows all transaction types by default (#41)
+- Category Over Time report: added type filter (expense/income/transfer) in the right filter panel (#41)
+
 ## [0.6.6]
 
 ### Changed
diff --git a/docs/guide-utilisateur.md b/docs/guide-utilisateur.md
index 23463d0..4053fee 100644
--- a/docs/guide-utilisateur.md
+++ b/docs/guide-utilisateur.md
@@ -252,7 +252,7 @@ Visualisez vos données financières avec des graphiques interactifs et comparez
 
 - Tendances mensuelles : revenus vs dépenses dans le temps (graphique en barres)
 - Dépenses par catégorie : répartition des dépenses (graphique circulaire)
-- Catégories dans le temps : suivez l'évolution de chaque catégorie (graphique en ligne)
+- Catégories dans le temps : suivez l'évolution de chaque catégorie (graphique en barres empilées), avec filtre par type (dépense/revenu/transfert)
 - Budget vs Réel : tableau comparatif mensuel et cumul annuel
 - Rapport dynamique : tableau croisé dynamique (pivot table) personnalisable
 - Motifs SVG (lignes, points, hachures) pour distinguer les catégories
diff --git a/src/components/reports/ReportFilterPanel.tsx b/src/components/reports/ReportFilterPanel.tsx
index ec0aea0..7f21a2a 100644
--- a/src/components/reports/ReportFilterPanel.tsx
+++ b/src/components/reports/ReportFilterPanel.tsx
@@ -2,6 +2,7 @@ import { useState } from "react";
 import { useTranslation } from "react-i18next";
 import { Filter, Search } from "lucide-react";
 import type { ImportSource } from "../../shared/types";
+import type { CategoryTypeFilter } from "../../hooks/useReports";
 
 interface ReportFilterPanelProps {
   categories: { name: string; color: string }[];
@@ -11,6 +12,8 @@ interface ReportFilterPanelProps {
   sources: ImportSource[];
   selectedSourceId: number | null;
   onSourceChange: (id: number | null) => void;
+  categoryType?: CategoryTypeFilter;
+  onCategoryTypeChange?: (type: CategoryTypeFilter) => void;
 }
 
 export default function ReportFilterPanel({
@@ -21,6 +24,8 @@ export default function ReportFilterPanel({
   sources,
   selectedSourceId,
   onSourceChange,
+  categoryType,
+  onCategoryTypeChange,
 }: ReportFilterPanelProps) {
   const { t } = useTranslation();
   const [search, setSearch] = useState("");
@@ -57,6 +62,28 @@ export default function ReportFilterPanel({
         </div>
       )}
 
+      {/* Type filter */}
+      {onCategoryTypeChange && (
+        <div className="bg-[var(--card)] border border-[var(--border)] rounded-xl overflow-hidden">
+          <div className="px-3 py-2.5 text-sm font-medium text-[var(--foreground)] flex items-center gap-2">
+            <Filter size={14} className="text-[var(--muted-foreground)]" />
+            {t("categories.type")}
+          </div>
+          <div className="border-t border-[var(--border)] px-2 py-2">
+            <select
+              value={categoryType ?? ""}
+              onChange={(e) => onCategoryTypeChange((e.target.value || null) as CategoryTypeFilter)}
+              className="w-full px-2 py-1.5 text-xs rounded-lg border border-[var(--border)] bg-[var(--background)] text-[var(--foreground)] focus:outline-none focus:ring-1 focus:ring-[var(--primary)]"
+            >
+              <option value="">{t("reports.filters.allTypes")}</option>
+              <option value="expense">{t("categories.expense")}</option>
+              <option value="income">{t("categories.income")}</option>
+              <option value="transfer">{t("categories.transfer")}</option>
+            </select>
+          </div>
+        </div>
+      )}
+
       {/* Category filter */}
       {categories.length > 0 && <div className="bg-[var(--card)] border border-[var(--border)] rounded-xl overflow-hidden">
         <button
diff --git a/src/hooks/useReports.ts b/src/hooks/useReports.ts
index b13f101..a5ec0b5 100644
--- a/src/hooks/useReports.ts
+++ b/src/hooks/useReports.ts
@@ -14,12 +14,15 @@ import { getExpensesByCategory } from "../services/dashboardService";
 import { getBudgetVsActualData } from "../services/budgetService";
 import { computeDateRange } from "../utils/dateRange";
 
+export type CategoryTypeFilter = "expense" | "income" | "transfer" | null;
+
 interface ReportsState {
   tab: ReportTab;
   period: DashboardPeriod;
   customDateFrom: string;
   customDateTo: string;
   sourceId: number | null;
+  categoryType: CategoryTypeFilter;
   monthlyTrends: MonthlyTrendItem[];
   categorySpending: CategoryBreakdownItem[];
   categoryOverTime: CategoryOverTimeData;
@@ -45,7 +48,8 @@ type ReportsAction =
   | { type: "SET_PIVOT_CONFIG"; payload: PivotConfig }
   | { type: "SET_PIVOT_RESULT"; payload: PivotResult }
   | { type: "SET_CUSTOM_DATES"; payload: { dateFrom: string; dateTo: string } }
-  | { type: "SET_SOURCE_ID"; payload: number | null };
+  | { type: "SET_SOURCE_ID"; payload: number | null }
+  | { type: "SET_CATEGORY_TYPE"; payload: CategoryTypeFilter };
 
 const now = new Date();
 const todayStr = `${now.getFullYear()}-${String(now.getMonth() + 1).padStart(2, "0")}-${String(now.getDate()).padStart(2, "0")}`;
@@ -57,6 +61,7 @@ const initialState: ReportsState = {
   customDateFrom: monthStartStr,
   customDateTo: todayStr,
   sourceId: null,
+  categoryType: null,
   monthlyTrends: [],
   categorySpending: [],
   categoryOverTime: { categories: [], data: [], colors: {}, categoryIds: {} },
@@ -97,6 +102,8 @@ function reducer(state: ReportsState, action: ReportsAction): ReportsState {
       return { ...state, period: "custom" as DashboardPeriod, customDateFrom: action.payload.dateFrom, customDateTo: action.payload.dateTo };
     case "SET_SOURCE_ID":
       return { ...state, sourceId: action.payload };
+    case "SET_CATEGORY_TYPE":
+      return { ...state, categoryType: action.payload };
     default:
       return state;
   }
@@ -115,6 +122,7 @@ export function useReports() {
     customTo?: string,
     pivotCfg?: PivotConfig,
     srcId?: number | null,
+    catType?: CategoryTypeFilter,
   ) => {
     const fetchId = ++fetchIdRef.current;
     dispatch({ type: "SET_LOADING", payload: true });
@@ -138,7 +146,7 @@ export function useReports() {
         }
         case "overTime": {
           const { dateFrom, dateTo } = computeDateRange(period, customFrom, customTo);
-          const data = await getCategoryOverTime(dateFrom, dateTo, undefined, srcId ?? undefined);
+          const data = await getCategoryOverTime(dateFrom, dateTo, undefined, srcId ?? undefined, catType ?? undefined);
           if (fetchId !== fetchIdRef.current) return;
           dispatch({ type: "SET_CATEGORY_OVER_TIME", payload: data });
           break;
@@ -170,8 +178,8 @@ export function useReports() {
   }, []);
 
   useEffect(() => {
-    fetchData(state.tab, state.period, state.budgetYear, state.budgetMonth, state.customDateFrom, state.customDateTo, state.pivotConfig, state.sourceId);
-  }, [state.tab, state.period, state.budgetYear, state.budgetMonth, state.customDateFrom, state.customDateTo, state.pivotConfig, state.sourceId, fetchData]);
+    fetchData(state.tab, state.period, state.budgetYear, state.budgetMonth, state.customDateFrom, state.customDateTo, state.pivotConfig, state.sourceId, state.categoryType);
+  }, [state.tab, state.period, state.budgetYear, state.budgetMonth, state.customDateFrom, state.customDateTo, state.pivotConfig, state.sourceId, state.categoryType, fetchData]);
 
   const setTab = useCallback((tab: ReportTab) => {
     dispatch({ type: "SET_TAB", payload: tab });
@@ -197,5 +205,9 @@ export function useReports() {
     dispatch({ type: "SET_SOURCE_ID", payload: id });
   }, []);
 
-  return { state, setTab, setPeriod, setCustomDates, setBudgetMonth, setPivotConfig, setSourceId };
+  const setCategoryType = useCallback((catType: CategoryTypeFilter) => {
+    dispatch({ type: "SET_CATEGORY_TYPE", payload: catType });
+  }, []);
+
+  return { state, setTab, setPeriod, setCustomDates, setBudgetMonth, setPivotConfig, setSourceId, setCategoryType };
 }
diff --git a/src/i18n/locales/en.json b/src/i18n/locales/en.json
index 7de1e70..e7b4011 100644
--- a/src/i18n/locales/en.json
+++ b/src/i18n/locales/en.json
@@ -370,7 +370,8 @@
       "title": "Categories",
       "search": "Search...",
       "all": "All",
-      "none": "None"
+      "none": "None",
+      "allTypes": "All types"
     },
     "bva": {
       "monthly": "Monthly",
diff --git a/src/i18n/locales/fr.json b/src/i18n/locales/fr.json
index 0f32f2c..af3cba4 100644
--- a/src/i18n/locales/fr.json
+++ b/src/i18n/locales/fr.json
@@ -370,7 +370,8 @@
       "title": "Catégories",
       "search": "Rechercher...",
       "all": "Toutes",
-      "none": "Aucune"
+      "none": "Aucune",
+      "allTypes": "Tous les types"
     },
     "bva": {
       "monthly": "Mensuel",
diff --git a/src/pages/ReportsPage.tsx b/src/pages/ReportsPage.tsx
index da975bd..1e34ebc 100644
--- a/src/pages/ReportsPage.tsx
+++ b/src/pages/ReportsPage.tsx
@@ -22,7 +22,7 @@ const TABS: ReportTab[] = ["trends", "byCategory", "overTime", "budgetVsActual",
 
 export default function ReportsPage() {
   const { t, i18n } = useTranslation();
-  const { state, setTab, setPeriod, setCustomDates, setBudgetMonth, setPivotConfig, setSourceId } = useReports();
+  const { state, setTab, setPeriod, setCustomDates, setBudgetMonth, setPivotConfig, setSourceId, setCategoryType } = useReports();
   const [sources, setSources] = useState<ImportSource[]>([]);
 
   useEffect(() => {
@@ -69,7 +69,7 @@ export default function ReportsPage() {
   const monthOptions = useMemo(() => buildMonthOptions(i18n.language), [i18n.language]);
 
   const hasCategories = ["byCategory", "overTime"].includes(state.tab) && filterCategories.length > 0;
-  const showFilterPanel = hasCategories || (state.tab === "trends" && sources.length > 1);
+  const showFilterPanel = hasCategories || state.tab === "overTime" || (state.tab === "trends" && sources.length > 1);
 
   return (
     <div className={state.isLoading ? "opacity-50 pointer-events-none" : ""}>
@@ -236,6 +236,8 @@ export default function ReportsPage() {
             sources={sources}
             selectedSourceId={state.sourceId}
             onSourceChange={setSourceId}
+            categoryType={state.tab === "overTime" ? state.categoryType : undefined}
+            onCategoryTypeChange={state.tab === "overTime" ? setCategoryType : undefined}
           />
         )}
       </div>
diff --git a/src/services/reportService.ts b/src/services/reportService.ts
index c455f82..20affe8 100644
--- a/src/services/reportService.ts
+++ b/src/services/reportService.ts
@@ -58,13 +58,20 @@ export async function getCategoryOverTime(
   dateTo?: string,
   topN: number = 50,
   sourceId?: number,
+  typeFilter?: "expense" | "income" | "transfer",
 ): Promise<CategoryOverTimeData> {
   const db = await getDb();
 
-  const whereClauses: string[] = ["t.amount < 0"];
+  const whereClauses: string[] = [];
   const params: unknown[] = [];
   let paramIndex = 1;
 
+  if (typeFilter) {
+    whereClauses.push(`COALESCE(c.type, 'expense') = $${paramIndex}`);
+    params.push(typeFilter);
+    paramIndex++;
+  }
+
   if (dateFrom) {
     whereClauses.push(`t.date >= $${paramIndex}`);
     params.push(dateFrom);
@@ -81,7 +88,7 @@ export async function getCategoryOverTime(
     paramIndex++;
   }
 
-  const whereSQL = `WHERE ${whereClauses.join(" AND ")}`;
+  const whereSQL = whereClauses.length > 0 ? `WHERE ${whereClauses.join(" AND ")}` : "";
 
   // Get top N categories by total spend
   const topCategories = await db.select<CategoryBreakdownItem[]>(