diff --git a/tests/conftest.py b/tests/conftest.py
@@ -105,12 +105,15 @@ def verify_threads_ended():
 
 
 @pytest.fixture
-def zc() -> Generator[Zeroconf]:
+def zc(verify_threads_ended: None) -> Generator[Zeroconf]:
     """Yield a loopback `Zeroconf` and close it on teardown.
 
     Replaces the inline `zc = Zeroconf(interfaces=["127.0.0.1"])` +
     explicit `zc.close()` pattern duplicated across the suite. Calling
     `zc.close()` inside a test is still safe — `close()` is idempotent.
+
+    Depends on `verify_threads_ended` so the instance is torn down before
+    the thread check runs.
     """
     zc = Zeroconf(interfaces=["127.0.0.1"])
     try:
@@ -120,7 +123,7 @@ def zc() -> Generator[Zeroconf]:
 
 
 @pytest_asyncio.fixture
-async def aiozc() -> AsyncGenerator[AsyncZeroconf]:
+async def aiozc(verify_threads_ended: None) -> AsyncGenerator[AsyncZeroconf]:
     """Yield a loopback `AsyncZeroconf` and close it on teardown.
 
     Replaces the inline `aiozc = AsyncZeroconf(interfaces=["127.0.0.1"])`

diff --git a/tests/services/test_browser.py b/tests/services/test_browser.py
@@ -54,11 +54,10 @@ def teardown_module():
         log.setLevel(original_logging_level)
 
 
-def test_service_browser_cancel_multiple_times():
+def test_service_browser_cancel_multiple_times(zc: Zeroconf) -> None:
     """Test we can cancel a ServiceBrowser multiple times before close."""
 
     # instantiate a zeroconf instance
-    zc = Zeroconf(interfaces=["127.0.0.1"])
     # start a browser
     type_ = "_hap._tcp.local."
 
@@ -73,14 +72,11 @@ class MyServiceListener(r.ServiceListener):
     browser.cancel()
     browser.cancel()
 
-    zc.close()
-
 
-def test_service_browser_cancel_context_manager():
+def test_service_browser_cancel_context_manager(zc: Zeroconf) -> None:
     """Test we can cancel a ServiceBrowser with it being used as a context manager."""
 
     # instantiate a zeroconf instance
-    zc = Zeroconf(interfaces=["127.0.0.1"])
     # start a browser
     type_ = "_hap._tcp.local."
 
@@ -102,8 +98,6 @@ class MyServiceListener(r.ServiceListener):
 
     assert cast(bool, browser.done) is True
 
-    zc.close()
-
 
 def test_service_browser_cancel_multiple_times_after_close():
     """Test we can cancel a ServiceBrowser multiple times after close."""
@@ -834,12 +828,10 @@ def on_service_state_change(zeroconf, service_type, state_change, name):
             await aiozc.async_close()
 
 
-def test_legacy_record_update_listener(quick_timing: None) -> None:
+def test_legacy_record_update_listener(zc: Zeroconf, quick_timing: None) -> None:
     """Test a RecordUpdateListener that does not implement update_records."""
 
     # instantiate a zeroconf instance
-    zc = Zeroconf(interfaces=["127.0.0.1"])
-
     with pytest.raises(RuntimeError):
         r.RecordUpdateListener().update_record(
             zc,
@@ -892,14 +884,11 @@ def on_service_state_change(zeroconf, service_type, state_change, name):
     # Removing a second time should not throw
     zc.remove_listener(listener)
 
-    zc.close()
-
 
-def test_service_browser_is_aware_of_port_changes():
+def test_service_browser_is_aware_of_port_changes(zc: Zeroconf) -> None:
     """Test that the ServiceBrowser is aware of port changes."""
 
     # instantiate a zeroconf instance
-    zc = Zeroconf(interfaces=["127.0.0.1"])
     # start a browser
     type_ = "_hap._tcp.local."
     registration_name = f"xxxyyy.{type_}"
@@ -955,14 +944,11 @@ def on_service_state_change(zeroconf, service_type, state_change, name):
     assert service_info.port == 400
     browser.cancel()
 
-    zc.close()
-
 
-def test_service_browser_listeners_update_service():
+def test_service_browser_listeners_update_service(zc: Zeroconf) -> None:
     """Test that the ServiceBrowser ServiceListener that implements update_service."""
 
     # instantiate a zeroconf instance
-    zc = Zeroconf(interfaces=["127.0.0.1"])
     # start a browser
     type_ = "_hap._tcp.local."
     registration_name = f"xxxyyy.{type_}"
@@ -1017,14 +1003,11 @@ def update_service(self, zc, type_, name) -> None:  # type: ignore[no-untyped-de
     ]
     browser.cancel()
 
-    zc.close()
-
 
-def test_service_browser_listeners_no_update_service():
+def test_service_browser_listeners_no_update_service(zc: Zeroconf) -> None:
     """A listener that ignores update events records only add/remove callbacks."""
 
     # instantiate a zeroconf instance
-    zc = Zeroconf(interfaces=["127.0.0.1"])
     # start a browser
     type_ = "_hap._tcp.local."
     registration_name = f"xxxyyy.{type_}"
@@ -1077,12 +1060,9 @@ def update_service(self, zc, type_, name) -> None:  # type: ignore[no-untyped-de
     ]
     browser.cancel()
 
-    zc.close()
-
 
-def test_service_browser_nsec_record_does_not_trigger_update():
+def test_service_browser_nsec_record_does_not_trigger_update(zc: Zeroconf) -> None:
     """NSEC records assert non-existence and must not fire ServiceStateChange.Updated."""
-    zc = Zeroconf(interfaces=["127.0.0.1"])
     type_ = "_hap._tcp.local."
     registration_name = f"xxxyyy.{type_}"
     callbacks: list[tuple[str, str, str]] = []
@@ -1144,24 +1124,21 @@ def update_service(self, zc, type_, name) -> None:  # type: ignore[no-untyped-de
         assert callbacks == [("add", type_, registration_name)]
     finally:
         browser.cancel()
-        zc.close()
 
 
-def test_service_browser_uses_non_strict_names():
+def test_service_browser_uses_non_strict_names(zc: Zeroconf) -> None:
     """Verify we can look for technically invalid names as we cannot change what others do."""
 
     # dummy service callback
     def on_service_state_change(zeroconf, service_type, state_change, name):
         pass
 
-    zc = r.Zeroconf(interfaces=["127.0.0.1"])
     browser = ServiceBrowser(zc, ["_tivo-videostream._tcp.local."], [on_service_state_change])
     browser.cancel()
 
     # Still fail on completely invalid
     with pytest.raises(r.BadTypeInNameException):
         browser = ServiceBrowser(zc, ["tivo-videostream._tcp.local."], [on_service_state_change])
-    zc.close()
 
 
 def test_group_ptr_queries_with_known_answers():
@@ -1408,11 +1385,10 @@ def send(out, addr=const._MDNS_ADDR, port=const._MDNS_PORT, v6_flow_scope=()):
     await aiozc.async_close()
 
 
-def test_service_browser_matching():
+def test_service_browser_matching(zc: Zeroconf) -> None:
     """Test that the ServiceBrowser matching does not match partial names."""
 
     # instantiate a zeroconf instance
-    zc = Zeroconf(interfaces=["127.0.0.1"])
     # start a browser
     type_ = "_http._tcp.local."
     registration_name = f"xxxyyy.{type_}"
@@ -1495,8 +1471,6 @@ def update_service(self, zc, type_, name) -> None:  # type: ignore[no-untyped-de
     ]
     browser.cancel()
 
-    zc.close()
-
 
 @patch.object(_engine, "_CACHE_CLEANUP_INTERVAL", 0.01)
 def test_service_browser_expire_callbacks():

diff --git a/tests/test_core.py b/tests/test_core.py
@@ -181,13 +181,9 @@ def test_use_asyncio_true_requires_running_loop():
         r.Zeroconf(interfaces=["127.0.0.1"], use_asyncio=True)
 
 
-def test_use_asyncio_default_starts_thread_without_loop():
+def test_use_asyncio_default_starts_thread_without_loop(zc: Zeroconf) -> None:
     """use_asyncio=None (default) keeps the historic auto-detect behavior."""
-    zc = r.Zeroconf(interfaces=["127.0.0.1"])
-    try:
-        assert zc._loop_thread is not None
-    finally:
-        zc.close()
+    assert zc._loop_thread is not None
 
 
 def test_async_updates_from_response():
@@ -396,9 +392,8 @@ def test_invalid_packets_ignored_and_does_not_cause_loop_exception():
     assert zc.cache.get(entry) is not None
 
 
-def test_goodbye_all_services():
+def test_goodbye_all_services(zc: Zeroconf) -> None:
     """Verify generating the goodbye query does not change with time."""
-    zc = Zeroconf(interfaces=["127.0.0.1"])
     out = zc.generate_unregister_all_services()
     assert out is None
     type_ = "_http._tcp.local."
@@ -429,15 +424,11 @@ def test_goodbye_all_services():
     assert out3 is None
     assert zc.registry.async_get_service_infos() == []
 
-    zc.close()
 
-
-def test_register_service_with_custom_ttl(quick_timing: None) -> None:
+def test_register_service_with_custom_ttl(zc: Zeroconf, quick_timing: None) -> None:
     """Test a registering a service with a custom ttl."""
 
     # instantiate a zeroconf instance
-    zc = Zeroconf(interfaces=["127.0.0.1"])
-
     # start a browser
     type_ = "_homeassistant._tcp.local."
     name = "MyTestHome"
@@ -456,15 +447,12 @@ def test_register_service_with_custom_ttl(quick_timing: None) -> None:
     record = zc.cache.get(info_service.dns_pointer())
     assert record is not None
     assert record.ttl == 3000
-    zc.close()
 
 
-def test_logging_packets(caplog: pytest.LogCaptureFixture, quick_timing: None) -> None:
+def test_logging_packets(zc: Zeroconf, caplog: pytest.LogCaptureFixture, quick_timing: None) -> None:
     """Test packets are only logged with debug logging."""
 
     # instantiate a zeroconf instance
-    zc = Zeroconf(interfaces=["127.0.0.1"])
-
     # start a browser
     type_ = "_logging._tcp.local."
     name = "TLD"
@@ -492,23 +480,18 @@ def test_logging_packets(caplog: pytest.LogCaptureFixture, quick_timing: None) -
     assert "Sending to" not in caplog.text
     logging.getLogger("zeroconf").setLevel(logging.DEBUG)
 
-    zc.close()
-
 
-def test_get_service_info_failure_path():
+def test_get_service_info_failure_path(zc: Zeroconf) -> None:
     """Verify get_service_info return None when the underlying call returns False."""
-    zc = Zeroconf(interfaces=["127.0.0.1"])
     assert zc.get_service_info("_neverused._tcp.local.", "xneverused._neverused._tcp.local.", 10) is None
-    zc.close()
 
 
 @pytest.mark.skipif(
     sys.platform == "win32",
     reason="multicast loopback on the 127.0.0.1-only socket is unreliable on GH Actions Windows runners",
 )
-def test_sending_unicast():
+def test_sending_unicast(zc: Zeroconf) -> None:
     """Test sending unicast response."""
-    zc = Zeroconf(interfaces=["127.0.0.1"])
     generated = r.DNSOutgoing(const._FLAGS_QR_RESPONSE)
     entry = r.DNSText(
         "didnotcrashincoming._crash._tcp.local.",
@@ -534,11 +517,8 @@ def test_sending_unicast():
 
     assert zc.cache.get(entry) is not None
 
-    zc.close()
 
-
-def test_tc_bit_defers():
-    zc = Zeroconf(interfaces=["127.0.0.1"])
+def test_tc_bit_defers(zc: Zeroconf) -> None:
     _wait_for_start(zc)
     type_ = "_tcbitdefer._tcp.local."
     name = "knownname"
@@ -634,11 +614,9 @@ def test_tc_bit_defers():
 
     # unregister
     zc.unregister_service(info)
-    zc.close()
 
 
-def test_tc_bit_defers_last_response_missing():
-    zc = Zeroconf(interfaces=["127.0.0.1"])
+def test_tc_bit_defers_last_response_missing(zc: Zeroconf) -> None:
     _wait_for_start(zc)
     type_ = "_knowndefer._tcp.local."
     name = "knownname"
@@ -751,12 +729,10 @@ def test_tc_bit_defers_last_response_missing():
 
     # unregister
     zc.registry.async_remove(info)
-    zc.close()
 
 
-def test_tc_bit_defer_window_is_bounded():
+def test_tc_bit_defer_window_is_bounded(zc: Zeroconf) -> None:
     """TC-deferral assembly window must not slide past first_arrival + max delay."""
-    zc = Zeroconf(interfaces=["127.0.0.1"])
     _wait_for_start(zc)
     type_ = "_boundeddefer._tcp.local."
     registration_name = f"knownname.{type_}"
@@ -797,7 +773,6 @@ def test_tc_bit_defer_window_is_bounded():
             assert protocol._timers[source_ip].when() <= first_when
 
     zc.registry.async_remove(info)
-    zc.close()
 
 
 def _make_distinct_tc_packets(count: int, name_prefix: str = "q") -> list[bytes]:
@@ -819,9 +794,8 @@ def _synthetic_source_ip(i: int) -> str:
     return f"192.0.2.{i - 512}"
 
 
-def test_tc_bit_per_addr_queue_is_bounded(quick_timing: None) -> None:
+def test_tc_bit_per_addr_queue_is_bounded(zc: Zeroconf, quick_timing: None) -> None:
     """Per-addr deferred queue must not grow past ``_MAX_DEFERRED_PER_ADDR``."""
-    zc = Zeroconf(interfaces=["127.0.0.1"])
     _wait_for_start(zc)
     protocol = zc.engine.protocols[0]
     source_ip = "203.0.113.21"
@@ -841,12 +815,9 @@ def test_tc_bit_per_addr_queue_is_bounded(quick_timing: None) -> None:
         retained = [incoming.data for incoming in protocol._deferred[source_ip]]
         assert retained == packets[: const._MAX_DEFERRED_PER_ADDR]
 
-    zc.close()
-
 
-def test_tc_bit_total_addrs_is_bounded(quick_timing: None) -> None:
+def test_tc_bit_total_addrs_is_bounded(zc: Zeroconf, quick_timing: None) -> None:
     """Distinct addrs with deferred state must not exceed ``_MAX_DEFERRED_ADDRS``."""
-    zc = Zeroconf(interfaces=["127.0.0.1"])
     _wait_for_start(zc)
     protocol = zc.engine.protocols[0]
 
@@ -865,12 +836,9 @@ def test_tc_bit_total_addrs_is_bounded(quick_timing: None) -> None:
         assert len(protocol._deferred) == const._MAX_DEFERRED_ADDRS
         assert len(protocol._timers) == const._MAX_DEFERRED_ADDRS
 
-    zc.close()
-
 
-def test_tc_bit_eviction_drops_oldest_addr(quick_timing: None) -> None:
+def test_tc_bit_eviction_drops_oldest_addr(zc: Zeroconf, quick_timing: None) -> None:
     """Adding a new addr at capacity drops the oldest insertion (FIFO)."""
-    zc = Zeroconf(interfaces=["127.0.0.1"])
     _wait_for_start(zc)
     protocol = zc.engine.protocols[0]
 
@@ -892,8 +860,6 @@ def test_tc_bit_eviction_drops_oldest_addr(quick_timing: None) -> None:
         assert new_addr in protocol._deferred
         assert len(protocol._deferred) == const._MAX_DEFERRED_ADDRS
 
-    zc.close()
-
 
 @pytest.mark.asyncio
 async def test_open_close_twice_from_async() -> None: