diff --git a/src/libutil/tests/tests.cc b/src/libutil/tests/tests.cc
index ffba832d8..35a5d27bb 100644
--- a/src/libutil/tests/tests.cc
+++ b/src/libutil/tests/tests.cc
@@ -587,4 +587,14 @@ namespace nix {
 
         ASSERT_EQ(filterANSIEscapes(s, true), "foo     bar     baz" );
     }
+
+    TEST(filterANSIEscapes, utf8) {
+        ASSERT_EQ(filterANSIEscapes("foobar", true, 5), "fooba");
+        ASSERT_EQ(filterANSIEscapes("fóóbär", true, 6), "fóóbär");
+        ASSERT_EQ(filterANSIEscapes("fóóbär", true, 5), "fóóbä");
+        ASSERT_EQ(filterANSIEscapes("fóóbär", true, 3), "fóó");
+        ASSERT_EQ(filterANSIEscapes("f€€bär", true, 4), "f€€b");
+        ASSERT_EQ(filterANSIEscapes("f𐍈𐍈bär", true, 4), "f𐍈𐍈b");
+    }
+
 }
diff --git a/src/libutil/util.cc b/src/libutil/util.cc
index 53342b5cb..01ab9111f 100644
--- a/src/libutil/util.cc
+++ b/src/libutil/util.cc
@@ -1409,7 +1409,28 @@ std::string filterANSIEscapes(const std::string & s, bool filterAll, unsigned in
             i++;
 
         else {
-            t += *i++; w++;
+            w++;
+            // Copy one UTF-8 character.
+            if ((*i & 0xe0) == 0xc0) {
+                t += *i++;
+                if (i != s.end() && ((*i & 0xc0) == 0x80)) t += *i++;
+            } else if ((*i & 0xf0) == 0xe0) {
+                t += *i++;
+                if (i != s.end() && ((*i & 0xc0) == 0x80)) {
+                    t += *i++;
+                    if (i != s.end() && ((*i & 0xc0) == 0x80)) t += *i++;
+                }
+            } else if ((*i & 0xf8) == 0xf0) {
+                t += *i++;
+                if (i != s.end() && ((*i & 0xc0) == 0x80)) {
+                    t += *i++;
+                    if (i != s.end() && ((*i & 0xc0) == 0x80)) {
+                        t += *i++;
+                        if (i != s.end() && ((*i & 0xc0) == 0x80)) t += *i++;
+                    }
+                }
+            } else
+                t += *i++;
         }
     }