diff --git a/src/tui.zig b/src/tui.zig
index e8e0389..c09d163 100644
--- a/src/tui.zig
+++ b/src/tui.zig
@@ -309,6 +309,7 @@ pub const App = struct {
 
     // Account filter state
     account_filter: ?[]const u8 = null, // active account filter (owned copy; null = all accounts)
+    filtered_positions: ?[]zfin.Position = null, // positions for filtered account (from positionsForAccount)
     account_list: std.ArrayList([]const u8) = .empty, // distinct accounts from portfolio lots (borrowed from portfolio)
     account_picker_cursor: usize = 0, // cursor position in picker (0 = "All accounts")
 
@@ -684,10 +685,15 @@ pub const App = struct {
 
     /// Set or clear the account filter. Owns the string via allocator.
     pub fn setAccountFilter(self: *App, name: ?[]const u8) void {
-        // Free the old owned copy
         if (self.account_filter) |old| self.allocator.free(old);
+        if (self.filtered_positions) |fp| self.allocator.free(fp);
+        self.filtered_positions = null;
+
         if (name) |n| {
             self.account_filter = self.allocator.dupe(u8, n) catch null;
+            if (self.portfolio) |pf| {
+                self.filtered_positions = pf.positionsForAccount(self.allocator, n) catch null;
+            }
         } else {
             self.account_filter = null;
         }
@@ -1347,6 +1353,7 @@ pub const App = struct {
         self.options_rows.deinit(self.allocator);
         self.account_list.deinit(self.allocator);
         if (self.account_filter) |af| self.allocator.free(af);
+        if (self.filtered_positions) |fp| self.allocator.free(fp);
         if (self.watchlist_prices) |*wp| wp.deinit();
         if (self.analysis_result) |*ar| ar.deinit(self.allocator);
         if (self.classification_map) |*cm| cm.deinit();
diff --git a/src/tui/portfolio_tab.zig b/src/tui/portfolio_tab.zig
index 9f0b85f..9c0af56 100644
--- a/src/tui/portfolio_tab.zig
+++ b/src/tui/portfolio_tab.zig
@@ -199,6 +199,7 @@ pub fn loadPortfolioData(app: *App) void {
 
     sortPortfolioAllocations(app);
     buildAccountList(app);
+    recomputeFilteredPositions(app);
     rebuildPortfolioRows(app);
 
     const summary = pf_data.summary;
@@ -288,10 +289,14 @@ pub fn rebuildPortfolioRows(app: *App) void {
 
             // Count lots for this symbol (filtered by account when filter is active)
             var lcount: usize = 0;
-            if (app.portfolio) |pf| {
-                for (pf.lots) |lot| {
-                    if (lot.security_type == .stock and std.mem.eql(u8, lot.priceSymbol(), a.symbol)) {
-                        if (matchesAccountFilter(app, lot.account)) lcount += 1;
+            if (findFilteredPosition(app, a.symbol)) |pos| {
+                lcount = pos.open_lots + pos.closed_lots;
+            } else if (app.account_filter == null) {
+                if (app.portfolio) |pf| {
+                    for (pf.lots) |lot| {
+                        if (lot.security_type == .stock and std.mem.eql(u8, lot.priceSymbol(), a.symbol)) {
+                            lcount += 1;
+                        }
                     }
                 }
             }
@@ -583,6 +588,26 @@ pub fn buildAccountList(app: *App) void {
     }
 }
 
+/// Recompute filtered_positions when portfolio or account filter changes.
+fn recomputeFilteredPositions(app: *App) void {
+    if (app.filtered_positions) |fp| app.allocator.free(fp);
+    app.filtered_positions = null;
+    const filter = app.account_filter orelse return;
+    const pf = app.portfolio orelse return;
+    app.filtered_positions = pf.positionsForAccount(app.allocator, filter) catch null;
+}
+
+/// Look up a symbol in the pre-computed filtered positions.
+/// Returns null if no filter is active or the symbol isn't in the filtered account.
+fn findFilteredPosition(app: *const App, symbol: []const u8) ?zfin.Position {
+    const fps = app.filtered_positions orelse return null;
+    for (fps) |pos| {
+        if (std.mem.eql(u8, pos.symbol, symbol) or std.mem.eql(u8, pos.lot_symbol, symbol))
+            return pos;
+    }
+    return null;
+}
+
 /// Check if a lot matches the active account filter.
 /// Returns true if no filter is active or the lot's account matches.
 fn matchesAccountFilter(app: *const App, account: ?[]const u8) bool {
@@ -592,25 +617,11 @@ fn matchesAccountFilter(app: *const App, account: ?[]const u8) bool {
 }
 
 /// Check if an allocation matches the active account filter.
-/// Uses the allocation's account field (which is "Multiple" for mixed-account positions).
-/// For "Multiple" accounts, we need to check if any lot with this symbol belongs to the filtered account.
+/// When filtered, checks against pre-computed filtered_positions.
 fn allocationMatchesFilter(app: *const App, a: zfin.valuation.Allocation) bool {
-    const filter = app.account_filter orelse return true;
-    // Simple case: allocation has a single account
-    if (!std.mem.eql(u8, a.account, "Multiple")) {
-        return std.mem.eql(u8, a.account, filter);
-    }
-    // "Multiple" account: check if any stock lot for this symbol belongs to the filtered account
-    if (app.portfolio) |pf| {
-        for (pf.lots) |lot| {
-            if (lot.security_type == .stock and std.mem.eql(u8, lot.priceSymbol(), a.symbol)) {
-                if (lot.account) |la| {
-                    if (std.mem.eql(u8, la, filter)) return true;
-                }
-            }
-        }
-    }
-    return false;
+    if (app.account_filter == null) return true;
+    if (app.filtered_positions == null) return false;
+    return findFilteredPosition(app, a.symbol) != null;
 }
 
 /// Account-filtered view of an allocation. When a position spans multiple accounts,
@@ -624,41 +635,24 @@ const FilteredAlloc = struct {
 
 /// Compute account-filtered values for an allocation.
 /// For single-account positions (or no filter), returns the allocation's own values.
-/// For "Multiple"-account positions with a filter, sums only the matching lots.
+/// For filtered views, uses pre-computed filtered_positions.
 fn filteredAllocValues(app: *const App, a: zfin.valuation.Allocation) FilteredAlloc {
-    const filter = app.account_filter orelse return .{
+    if (app.account_filter == null) return .{
         .shares = a.shares,
         .cost_basis = a.cost_basis,
         .market_value = a.market_value,
         .unrealized_gain_loss = a.unrealized_gain_loss,
     };
-    if (!std.mem.eql(u8, a.account, "Multiple")) return .{
-        .shares = a.shares,
-        .cost_basis = a.cost_basis,
-        .market_value = a.market_value,
-        .unrealized_gain_loss = a.unrealized_gain_loss,
-    };
-    // Sum values from only the lots matching the filter
-    var shares: f64 = 0;
-    var cost: f64 = 0;
-    if (app.portfolio) |pf| {
-        for (pf.lots) |lot| {
-            if (lot.security_type != .stock) continue;
-            if (!std.mem.eql(u8, lot.priceSymbol(), a.symbol)) continue;
-            if (!lot.isOpen()) continue;
-            const la = lot.account orelse "";
-            if (!std.mem.eql(u8, la, filter)) continue;
-            shares += lot.shares;
-            cost += lot.shares * lot.open_price;
-        }
+    if (findFilteredPosition(app, a.symbol)) |pos| {
+        const mv = pos.shares * a.current_price * pos.price_ratio;
+        return .{
+            .shares = pos.shares,
+            .cost_basis = pos.total_cost,
+            .market_value = mv,
+            .unrealized_gain_loss = mv - pos.total_cost,
+        };
     }
-    const mv = shares * a.current_price * a.price_ratio;
-    return .{
-        .shares = shares,
-        .cost_basis = cost,
-        .market_value = mv,
-        .unrealized_gain_loss = mv - cost,
-    };
+    return .{ .shares = 0, .cost_basis = 0, .market_value = 0, .unrealized_gain_loss = 0 };
 }
 
 /// Totals for the filtered account view (stocks + cash + CDs + options).
@@ -896,38 +890,20 @@ pub fn drawContent(app: *App, arena: std.mem.Allocator, buf: []vaxis.Cell, width
                             if (app.portfolio) |pf| {
                                 for (pf.lots) |lot| {
                                     if (lot.security_type == .stock and std.mem.eql(u8, lot.priceSymbol(), a.symbol)) {
-                                        const ds = lot.open_date.format(&pos_date_buf);
-                                        const indicator = fmt.capitalGainsIndicator(lot.open_date);
-                                        date_col = std.fmt.allocPrint(arena, "{s} {s}", .{ ds, indicator }) catch ds;
-                                        acct_col = lot.account orelse "";
-                                        break;
-                                    }
-                                }
-                            }
-                        } else {
-                            // Multi-lot: show account if all lots share the same one
-                            if (app.portfolio) |pf| {
-                                var common_acct: ?[]const u8 = null;
-                                var mixed = false;
-                                for (pf.lots) |lot| {
-                                    if (lot.security_type == .stock and std.mem.eql(u8, lot.priceSymbol(), a.symbol)) {
-                                        if (common_acct) |ca| {
-                                            const la = lot.account orelse "";
-                                            if (!std.mem.eql(u8, ca, la)) {
-                                                mixed = true;
-                                                break;
-                                            }
-                                        } else {
-                                            common_acct = lot.account orelse "";
+                                        if (matchesAccountFilter(app, lot.account)) {
+                                            const ds = lot.open_date.format(&pos_date_buf);
+                                            const indicator = fmt.capitalGainsIndicator(lot.open_date);
+                                            date_col = std.fmt.allocPrint(arena, "{s} {s}", .{ ds, indicator }) catch ds;
+                                            acct_col = lot.account orelse "";
+                                            break;
                                         }
                                     }
                                 }
-                                if (!mixed) {
-                                    acct_col = common_acct orelse "";
-                                } else {
-                                    acct_col = "Multiple";
-                                }
                             }
+                        } else if (app.account_filter) |af| {
+                            acct_col = af;
+                        } else {
+                            acct_col = a.account;
                         }
 
                         const display_weight = if (app.account_filter != null and filtered_total_for_weight > 0)
@@ -1254,6 +1230,7 @@ pub fn reloadPortfolioFile(app: *App) void {
 
     sortPortfolioAllocations(app);
     buildAccountList(app);
+    recomputeFilteredPositions(app);
     rebuildPortfolioRows(app);
 
     // Invalidate analysis data -- it holds pointers into old portfolio memory