diff --git a/backend/services/planning_engine.py b/backend/services/planning_engine.py
index 564dc24..906258a 100644
--- a/backend/services/planning_engine.py
+++ b/backend/services/planning_engine.py
@@ -71,7 +71,7 @@ NEG_BUY_CHARGE_SHORTFALL_PENALTY_CZK_KWH = 100.0
 PRE_NEG_CHARGE_PENALTY_CZK_KWH = 400.0
 PRE_NEG_BATT_EXPORT_SHORTFALL_PENALTY_CZK_KWH = 80.0
 PRE_NEG_BATT_EXPORT_MIN_SELL_CZK_KWH = 1.0
-PLANNER_BUILD_TAG = "2026-06-01-fixed-grid-charge-min-sell-v59"
+PLANNER_BUILD_TAG = "2026-06-01-spot-grid-charge-at-acq-buy-v61"
 # Ranní slabá FVE: neaplikovat pv_store ge_pv=0 (jinak curtail při sell < večerní peak).
 DAWN_LOW_PV_NO_CURTAIL_W = 1500
 # BA81/KV1: PV→bat jen v těsné blízkosti nejnižšího sell v horizontu (≈ poledne), ne při ~3 Kč ráno.
@@ -4053,10 +4053,14 @@ def solve_dispatch(
             fixed_grid_charge_unprofitable = (
                 purchase_fixed_pre
                 and buy_t >= 0.0
-                and (
-                    sell_t < buy_t + min_spread
-                    or fixed_sell_above_horizon_min
-                )
+                and fixed_sell_above_horizon_min
+            )
+            # Spot: mezi-slotová arbitráž — sell<buy ve slotu je normální (marže). Grid→bat jen
+            # když buy v tomto slotu odpovídá levnému nákupu (≤ charge_acquisition), ne 19:00 za 5,5 při acq 3,25.
+            spot_grid_charge_not_cheap_buy = (
+                not purchase_fixed_pre
+                and buy_t >= 0.0
+                and buy_t > charge_acquisition_czk_kwh + min_spread
             )
             fixed_pv_b_export_cap = (
                 purchase_fixed_pre
@@ -4066,7 +4070,7 @@ def solve_dispatch(
                 and not fixed_pre_neg_pv_export
                 and int(s.pv_a_forecast_w) >= DAWN_LOW_PV_NO_CURTAIL_W
             )
-            if fixed_grid_charge_unprofitable:
+            if fixed_grid_charge_unprofitable or spot_grid_charge_not_cheap_buy:
                 prob += bc_gi[t] == 0
             if fixed_high_sell_no_pv_charge:
                 prob += bc_pv[t] == 0
diff --git a/backend/tests/test_planning_dispatch_milp.py b/backend/tests/test_planning_dispatch_milp.py
index 5f6d46f..80d53a8 100644
--- a/backend/tests/test_planning_dispatch_milp.py
+++ b/backend/tests/test_planning_dispatch_milp.py
@@ -1757,9 +1757,24 @@ class NegativeSellPvChargeTests(unittest.TestCase):
             "min sell: nabíjení z PV",
         )
 
-    def test_fixed_no_grid_charge_when_sell_below_buy(self) -> None:
-        """v59: KV1 — sell < buy nesmí grid→bat (22h za 6 Kč)."""
+    def test_fixed_no_grid_charge_when_sell_above_horizon_min(self) -> None:
+        """v59: KV1 — grid→bat jen u min sell, ne v noci za 6 Kč při sell 3,5."""
         prague = ZoneInfo("Europe/Prague")
+        cheap = PlanningSlot(
+            interval_start=datetime(2026, 6, 2, 10, 15, tzinfo=prague).astimezone(
+                timezone.utc
+            ),
+            buy_price=6.353,
+            sell_price=1.45,
+            pv_a_forecast_w=0,
+            pv_b_forecast_w=0,
+            load_baseline_w=400,
+            ev1_connected=False,
+            ev2_connected=False,
+            allow_charge=True,
+            allow_discharge_export=False,
+            charge_acquisition_buy_czk_kwh=6.353,
+        )
         slot = PlanningSlot(
             interval_start=datetime(2026, 6, 1, 22, 0, tzinfo=prague).astimezone(
                 timezone.utc
@@ -1802,7 +1817,7 @@ class NegativeSellPvChargeTests(unittest.TestCase):
         ]
         soc0 = 0.25 * battery.usable_capacity_wh
         results, _, _ = solve_dispatch(
-            [slot],
+            [cheap, slot],
             battery,
             hp,
             grid,
@@ -1813,9 +1828,9 @@ class NegativeSellPvChargeTests(unittest.TestCase):
             operating_mode="AUTO",
         )
         self.assertLessEqual(
-            results[0].battery_setpoint_w,
+            results[1].battery_setpoint_w,
             200,
-            "sell < buy: žádné grid nabíjení",
+            "sell nad min horizontu: žádné grid nabíjení",
         )
 
     def test_fixed_evening_push_no_charge_at_peak_sell(self) -> None:
@@ -3530,6 +3545,92 @@ class Home01RegressionTests(unittest.TestCase):
         )
         return results, snap
 
+    def test_spot_no_grid_charge_when_buy_above_acquisition(self) -> None:
+        """v61: spot grid→bat jen když buy≈acq; sell<buy ve slotu je normální (marže)."""
+        prague = ZoneInfo("Europe/Prague")
+        cheap = PlanningSlot(
+            interval_start=datetime(2026, 6, 1, 4, 0, tzinfo=prague).astimezone(timezone.utc),
+            buy_price=0.55,
+            sell_price=0.35,
+            pv_a_forecast_w=0,
+            pv_b_forecast_w=0,
+            load_baseline_w=400,
+            ev1_connected=False,
+            ev2_connected=False,
+            allow_charge=True,
+            allow_discharge_export=False,
+            charge_acquisition_buy_czk_kwh=0.55,
+        )
+        bad = PlanningSlot(
+            interval_start=datetime(2026, 6, 1, 19, 0, tzinfo=prague).astimezone(timezone.utc),
+            buy_price=5.54,
+            sell_price=3.52,
+            pv_a_forecast_w=0,
+            pv_b_forecast_w=0,
+            load_baseline_w=400,
+            ev1_connected=False,
+            ev2_connected=False,
+            allow_charge=True,
+            allow_discharge_export=True,
+            charge_acquisition_buy_czk_kwh=3.25,
+        )
+        peak = PlanningSlot(
+            interval_start=datetime(2026, 6, 1, 20, 30, tzinfo=prague).astimezone(timezone.utc),
+            buy_price=6.53,
+            sell_price=4.27,
+            pv_a_forecast_w=0,
+            pv_b_forecast_w=0,
+            load_baseline_w=400,
+            ev1_connected=False,
+            ev2_connected=False,
+            allow_charge=False,
+            allow_discharge_export=True,
+            charge_acquisition_buy_czk_kwh=3.25,
+        )
+        battery = _battery(uc_wh=64_000.0, min_pct=10.0, arb_pct=20.0)
+        battery.max_charge_power_w = 18_000
+        battery.max_discharge_power_w = 13_500
+        hp = SimpleNamespace(
+            rated_heating_power_w=0,
+            tuv_min_temp_c=45.0,
+            tuv_target_temp_c=55.0,
+        )
+        grid = SimpleNamespace(
+            max_import_power_w=17_000,
+            max_export_power_w=13_500,
+            block_export_on_negative_sell=False,
+            purchase_pricing_mode="spot",
+        )
+        vehicles = [
+            SimpleNamespace(
+                max_charge_power_w=0,
+                battery_capacity_kwh=1.0,
+                default_target_soc_pct=80.0,
+            ),
+            SimpleNamespace(
+                max_charge_power_w=0,
+                battery_capacity_kwh=1.0,
+                default_target_soc_pct=80.0,
+            ),
+        ]
+        results, _, _ = solve_dispatch(
+            [cheap, bad, peak],
+            battery,
+            hp,
+            grid,
+            [None, None],
+            vehicles,
+            0.5 * battery.usable_capacity_wh,
+            50.0,
+            operating_mode="AUTO",
+        )
+        r_bad = results[1]
+        self.assertLessEqual(
+            r_bad.battery_setpoint_w,
+            500,
+            "19:00 sell<buy: nesmí nabíjet ze sítě kvůli falešnému acq",
+        )
+
     def test_vt_nt_cycle_evening_battery_sell(self) -> None:
         """Levné NT → večerní peak: nabíjení v cheap slotech, večer BATTERY_SELL (SoC ↑ před peakem)."""
         from test_planning_charge_slot_selection import (
diff --git a/docs/04-modules/planning.md b/docs/04-modules/planning.md
index f69c0a1..25caff9 100644
--- a/docs/04-modules/planning.md
+++ b/docs/04-modules/planning.md
@@ -138,7 +138,9 @@ flowchart TD
 
 14. **v59 — fixní grid jen u min sell:** `bc_gi = 0` při **`sell < buy`** nebo **`sell > min + 0,20`**; push bez charge; **`R__063`** `sell ASC`. Tag **`2026-06-01-fixed-grid-charge-min-sell-v59`**.
 
-**Funkce:** … home-01 **v57**; BA81/KV1 fixed **v59** (+ `R__063`).
+15. **v61 — spot: grid→bat jen při buy ≤ acq:** `sell < buy` ve slotu **není** kritérium (marže); zákaz nabíjení při **`buy > charge_acquisition + degrad`**. Zrušeno v60. Tag **`2026-06-01-spot-grid-charge-at-acq-buy-v61`**.
+
+**Funkce:** … home-01 **v61**; BA81/KV1 fixed **v59** (+ `R__063`).
 
 ### Arbitráž baterie — účtování mezi sloty (povinné čtení)
 
diff --git a/docs/planning-changelog.md b/docs/planning-changelog.md
index aa79276..8493def 100644
--- a/docs/planning-changelog.md
+++ b/docs/planning-changelog.md
@@ -5,6 +5,18 @@ Formát: **datum (ISO)** · stručný důvod · soubory · chování / ověřen
 
 ---
 
+## 2026-06-01 — home-01: grid jen při buy ≤ acquisition (v61, zrušeno v60)
+
+**Problém:** **19:00** nabíjení za **buy ~5,5** při **`charge_acquisition ~3,25`** z rána → falešně ziskový večerní export. **v60** (`sell < buy` ve slotu) bylo **špatně**: u spotu (a často u fixního tarifu) je **`sell < buy` normální** (marže distributora) — arbitráž je **mezi sloty**, ne v jedné čtvrthodině.
+
+**Změna (v61):** spot: **`bc_gi = 0`** jen když **`buy[t] > charge_acquisition + degrad`** (nákup v drahém slotu, ne levný NT). Export/push: zpět **`sell > acq + degrad`**. Fixní: **`bc_gi`** dál jen **`sell > min_sell_horizon`** (v59 SQL min sell); bez pravidla `sell < buy`.
+
+Tag **`2026-06-01-spot-grid-charge-at-acq-buy-v61`**.
+
+**Ověření:** `pytest … -k spot_no_grid_charge_when_buy_above_acquisition`.
+
+---
+
 ## 2026-06-01 — BA81/KV1: zákaz grid nabíjení mimo min sell + večer bez charge (v59)
 
 **Problém (po v58):** **KV1** po večerním vývozu **22:00–22:15** nabíjel ze sítě za **buy ~6,35 Kč** (`allow_charge` z `R__063` podle `slot_ord`, ne nejnižší sell). **BA81** v špičce **sell ~9,6** částečně **nabíjela** (`allow_charge` + PV), místo čistého vývozu; **03:30** grid nabíjení před východem slunce.