diff --git a/deps_src/libnest2d/include/libnest2d/placers/nfpplacer.hpp b/deps_src/libnest2d/include/libnest2d/placers/nfpplacer.hpp
index dc7733ebd6..cf66c4c97e 100644
--- a/deps_src/libnest2d/include/libnest2d/placers/nfpplacer.hpp
+++ b/deps_src/libnest2d/include/libnest2d/placers/nfpplacer.hpp
@@ -1111,7 +1111,27 @@ private:
         default: ; // DONT_ALIGN
         }
 
-        auto d = cb - ci;       
+        auto d = cb - ci;
+
+        // Keep the pile on the bin. A target near an edge (a belt printer starts its parts
+        // at the leading end of the belt) would otherwise centre a pile that is larger than
+        // the room around that point on it and push part of the pile off the bed. The pile
+        // stops at the edge instead; the items' boxes carry their inflation, which is the
+        // margin left there. A pile that does not fit along an axis is centred on it.
+        {
+            auto on_bin = [](Coord lo, Coord hi, Coord bin_lo, Coord bin_hi, Coord shift) {
+                if (hi - lo >= bin_hi - bin_lo)
+                    return (bin_lo + bin_hi) / 2 - (lo + hi) / 2;
+                if (lo + shift < bin_lo)
+                    shift = bin_lo - lo;
+                if (hi + shift > bin_hi)
+                    shift = bin_hi - hi;
+                return shift;
+            };
+            setX(d, on_bin(getX(bb.minCorner()), getX(bb.maxCorner()), getX(bbin.minCorner()), getX(bbin.maxCorner()), getX(d)));
+            setY(d, on_bin(getY(bb.minCorner()), getY(bb.maxCorner()), getY(bbin.minCorner()), getY(bbin.maxCorner()), getY(d)));
+            cb = ci + d;
+        }
 
         // BBS make sure the item won't clash with excluded regions
         // do we have wipe tower after arranging?
diff --git a/tests/libslic3r/test_arrange.cpp b/tests/libslic3r/test_arrange.cpp
index 3906cba8ba..a8bc56d2d5 100644
--- a/tests/libslic3r/test_arrange.cpp
+++ b/tests/libslic3r/test_arrange.cpp
@@ -1,3 +1,4 @@
+#include <limits>
 #include <catch2/catch_all.hpp>
 
 #include "libslic3r/Arrange.hpp"
@@ -259,6 +260,31 @@ TEST_CASE("Arrange aligns the pile to a custom center", "[Arrange]")
     require_no_overlap(items);
 }
 
+// A belt printer starts its parts at the leading end of the belt (best_object_pos 0.5, 0.05).
+// Centring a pile on a point that close to the edge pushed everything longer than the room
+// around it off the bed: four 90 mm parts on a 95 x 500 mm belt ended with one across the
+// edge and one outside, with 290 mm of belt free behind them. The pile stops at the edge.
+TEST_CASE("Arrange keeps a pile aligned near an edge on the bed", "[Arrange]")
+{
+    const BoundingBox belt   = bed(95, 500);
+    ArrangePolygons   items  = squares(4, 90.);
+    ArrangeParams     params = quiet_params(scaled(2.));
+    params.align_center      = Vec2d(0.5, 0.05);
+
+    arrange(items, belt, params);
+
+    coord_t lowest = std::numeric_limits<coord_t>::max();
+    for (const ArrangePolygon &ap : items) {
+        REQUIRE(ap.bed_idx == 0);
+        const BoundingBox bb = ap.transformed_poly().contour.bounding_box();
+        CHECK(belt.contains(bb));
+        lowest = std::min(lowest, bb.min.y());
+    }
+    // Snapped to the edge it was aimed at, less the spacing margin, not re-centred.
+    CHECK(lowest < scaled(10.));
+    require_no_overlap(items);
+}
+
 TEST_CASE("Sequential print floors the object distance by object height", "[Arrange]")
 {
     // The only place sequential-print clearance is enforced. The arrange menu offers