Product Library / Thermostats

Discontinued

Honeywell Home T9 Smart Thermostat

Compiled by SmartHomeWorkflow Research · Honeywell Home (Resideo) · Thermostats · ~$209.99 (Resideo's last published list price for the with-sensor kit (RCHT9610WFSW2003/U) — the configuration this profile describes. Discontinued: Resideo shows every T9 variant out of stock, so what a buyer actually pays is third-party remaining stock, which is volatile and frequently lower. Never treated as a live price.)

Raised from unknown — the axis had never been checked (verifiedAt null, source empty). ⚠ The dated forward risk, recorded rather than smoothed over: the forced app migration to First Alert by Resideo is still ahead and will require re-adding the device and re-enrolling in utility demand-response. That is a scheduled disruption for Alexa, Google, Apple Home and SmartThings households alike, not a present degradation — re-check this axis when the migration date is published. Discontinued as of late 2025 and now out of stock at Resideo itself across every variant — you are buying third-party remaining stock, with a forced app migration ahead, and it will never get Matter; Matter buyers should look at the X8S or X2S instead. And the room sensors — the reason to choose this thermostat — are only visible to Alexa and Google: Apple Home, SmartThings and IFTTT can change the temperature but cannot see a single sensor reading.

Exactly which product this is[1][7]

Model number
RCHT9610WFSW2003/U
Generation
Not established
Region this page covers
Not established
Also sold or listed as
Not established

“Not established” means we have not sourced that detail yet — not that the product has no model number, generation or regional variant. We publish the gap rather than filling it.

Compatibility

EcosystemSupportThe catch
Amazon AlexaWorksWorks with this ecosystem[8]Full support
Google HomeWorksWorks with this ecosystem[9]Full support
Apple HomePartialPartial support — see the catch[2][4]Apple Home can change setpoints but CANNOT see the T9's remote room sensors — the feature the product is named for and bought for. Resideo says so in its own words: 'HomeKit, IFTTT, SmartThings and Cortana will allow you to change setpoints on your thermostat, but cannot view the sensor readings at this time', with only Alexa and Google able to view and control both. HomeKit itself was added by free firmware update (Nov 2021), so older press saying 'no HomeKit' is outdated — the limitation is about sensors, not about HomeKit support.
SmartThingsPartialPartial support — see the catch[2][10]Cloud-linked service, and SmartThings can only change setpoints — it cannot see the T9's remote room sensors, which are the product's headline feature. Resideo's own words: 'HomeKit, IFTTT, SmartThings and Cortana will allow you to change setpoints on your thermostat, but cannot view the sensor readings at this time.' The same limitation applies to Apple Home; only Alexa and Google can see the sensors.
Home AssistantWorksWorks with this ecosystem[3][5]Core 'Honeywell Lyric' integration is cloud-polling and needs a Resideo developer API key — real friction; HomeKit Controller integration is the local alternative

Protocols: WIFI[1]

What it can do[12]

You can tell it to

  • Target temperature
  • HVAC mode
  • Fan mode

It reports

  • Temperature reading
  • Humidity reading

Listed capabilities are what we could establish from vendor documentation. An ability missing here is unestablished — not necessarily absent.

Subscription reality[1]

✓ Works without a subscription: Yes.

Vendor account required: Not established — we have not sourced this yet.

No subscription for app control, sensors, or voice integrations

Maintenance reality[1][6]

Who it's for

Alexa or Google households that want room-sensor comfort balancing at a clearance price and are comfortable buying an end-of-line product. Apple Home and SmartThings households should look elsewhere for this specific job — those platforms get setpoint control without the sensor readings the T9 exists to provide.

Sources & method

Numbered sources below back the facts marked with the matching number above. This is a research profile: compiled from manufacturer documentation, certification registries, and published testing — we state facts, not verdicts, and we have not physically tested this unit. How we work →

  1. [1] Resideo honeywellhome.com T9 product page and its structured product endpoint (read 2026-08-08): product available false; variants RCHT9610WFSW2003/U 'T9 Smart Thermostat with Sensor' $209.99, RCHT9510WFW2001/U 'T9 Smart Thermostat' $179.99, RCHT9610WFSW2019/W Canada (no price), SMHOM9510KIT and SMHOM9610KIT C-wire-adaptor kits $209.99 — all unavailable; schema.org offer data availability 'OutOfStock', seller Honeywell Home, sku/mpn RCHT9610WFSW2003/U; in-box list 'Thermostat; Installation guide; UWP Wall Plate; Wireless Sensor; Screws; Anchors; Wire Labels; C-Wire Adapter'; ecosystem list Amazon Alexa, Google Assistant, Microsoft Cortana, Samsung SmartThings, IFTTT, Apple HomeKit; no subscription, plan or tier named anywhere; no Matter or Thread claim anywhere on the page — vendor-page research, verified 2026-08-08
    Backs: Product identity, Price, Protocols, Subscription, Maintenance, Market availability, Service status, Research status
  2. [2] Resideo official support article 'Which smart home apps are compatible with the T9 Smart Thermostat and T10 Pro Smart Thermostat?' (honeywellhome.com, Last Updated: September 2, 2025, re-read 2026-08-08): 'Currently only Amazon Alexa and Google Assistant can view and control both the thermostat and sensors.' — 'HomeKit, IFTTT, SmartThings and Cortana will allow you to change setpoints on your thermostat, but cannot view the sensor readings at this time.' — vendor-and-ecosystem-page research, verified 2026-08-08
    Backs: Apple Home compatibility, SmartThings compatibility
  3. [3] Home Assistant official documentation for the Honeywell Lyric integration (read 2026-08-08): 'introduced in Home Assistant 2021.3, and it's used by 1282 active installations', IoT class 'Cloud Polling'; setup requires Client ID and Client Secret corresponding to the Consumer Key and Consumer Secret from an app created on the Honeywell developer site — vendor-and-ecosystem-page research, verified 2026-08-08
    Backs: Service status, Home Assistant compatibility
  4. [4] Resideo tech doc 33-00565EFS 'T9 & T10 Apple HomeKit Setup' + honeywellhome.com HomeKit support article; firmware timing Nov 2021 press-reported — vendor-page research, verified 2026-07-15
    Backs: Apple Home compatibility
  5. [5] home-assistant.io/integrations/lyric (core since 2021.3; T9 incl. room-sensor priority; cloud-polling, developer key required) — vendor-page research, verified 2026-07-15
    Backs: Home Assistant compatibility
  6. [6] First Alert / honeywellhome.com support articles on app migration; official sensor pages (AAA x2, ~1yr, 20 sensors max, 200 ft) — vendor-page research, verified 2026-07-15
    Backs: Maintenance
  7. [7] honeywellhome.com T9 product page (discontinued banner, SKU RCHT9610WFSW2003/U, ecosystem list, in-box contents) + honeywellstore.com ('DISCONTINUED', X8S named as replacement) — vendor-page research, verified 2026-07-15
    Backs: Product identity, Market availability
  8. [8] Resideo official T9/T10 compatibility support article (honeywellhome.com, 'Which smart home apps are compatible with the T9 and T10 Pro', last updated 2025-09-02): Amazon Alexa can 'view and control both the thermostat and sensors' — full native integration including the T9's remote sensors — vendor-and-ecosystem-page research, verified 2026-08-20
    Backs: Amazon Alexa compatibility
  9. [9] Resideo official T9/T10 compatibility support article (last updated 2025-09-02): Google Assistant, like Alexa, can 'view and control both the thermostat and sensors' — one of only two platforms with full capability — vendor-and-ecosystem-page research, verified 2026-08-20
    Backs: Google Home compatibility
  10. [10] Resideo official T9/T10 compatibility support article (last updated 2025-09-02): 'HomeKit, IFTTT, SmartThings and Cortana will allow you to change setpoints on your thermostat, but cannot view the sensor readings at this time' — a real limit, so the previous 'full' overstated it. Samsung's Honeywell Home partner page (partners.smartthings.com/partners/honeywell-home) lists no specific thermostat models. WAS CUSTOMER-FACING WRONG: the cell claimed full — vendor-and-ecosystem-page research, verified 2026-07-21
    Backs: SmartThings compatibility
  11. [11] home-assistant.io lyric integration plus honeywellhome.com T9 product page, compatibility blog and the SmartThings partner listing, re-read 2026-08-18 — vendor-page research, verified 2026-08-18
  12. [12] honeywellhome.com/products/t9-smart-thermostat, read 2026-08-20: the Resideo App lets you "manage your Honeywell Home devices in the easy-to-use app"; system modes enumerated as "Heat; Cool; Auto; Off; Emergency Heat"; fan function enumerated as "On; Auto; Circulating"; "indoor outdoor temp humidity" monitoring with a wireless sensor and a multi-room display "on the thermostat's touchscreen — or in the app". Works with Amazon Alexa, Google Assistant, Samsung SmartThings, IFTTT and Apple HomeKit. — vendor-page research, verified 2026-08-20
    Backs: Capabilities
  13. [13] honeywellhome.com's T9 product page, read 2026-08-20. Its specification table gives "WiFi: Yes" with "802.11b; 802.11g; 802.11n; 2.4GHz range; 5GHz range", and its works-with list names Amazon Alexa, Google Assistant, Microsoft Cortana, Samsung SmartThings, IFTTT and Apple HomeKit. No gateway, bridge or hub appears in either. — vendor-page research (BQ-191 provider backfill, population (b): the `hubs` axis), verified 2026-08-20
    Backs: Required hub or bridge
  14. [14] Three Resideo first-party surfaces, all read 2026-08-20 and none carrying a support period. (1) resideo.com/us/en/support/security/ publishes no defined support duration, no end-of-support policy and no per-model timeframe. (2) The Resideo responsible-disclosure page describes its Coordinated Vulnerability Disclosure process and PSIRT investigation, and commits to no timeline for patch availability and no duration of support. (3) Resideo's two published end-of-support announcements are the informative part: the legacy Wi-Fi Water Leak Detectors ended installation support because "The security certificates used by these devices have expired" and "the certificates cannot be updated", with devices not online as of January 12, 2026 no longer installable; and the Honeywell Home Smart Security Kit ended October 31, 2024 because a certificate "was created and maintained by Honeywell" and Honeywell chose not to renew it. — vendor policy-page research (BQ-192 security-support sweep, method note 69 rungs a–c), verified 2026-08-20
    Backs: Security-update support period

Compatibility and lifecycle information reflects the last-verified date above and can change without notice (firmware updates, cloud-service changes, discontinuations). It is provided as-is, for information — verify with the manufacturer before purchasing. Spot an error? Tell us and we'll fix it. Full terms: Terms of Service.

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