Car-Safety.Org Information on LATCH ( Lower
Top tethers and LATCH are two important improvements in carseat safety and convenience. LATCH has been available in most passenger vehicles since model year 2003. Tether anchors have been available since model year 2000. This article addresses many questions and concerns about this system.
Flexible LATCH (NHTSA)
Top Tether Anchor Photo (NHTSA)
LATCH Lower Anchor Photo (NHTSA)
A top tether (or top strap) is the supplemental attachment now standard on almost every new carseat in the USA. Top tethers can be used with either the seat belt or with the lower anchors (as part of the LATCH system). In other countries, their use may be required by law. A top tether is simply a strap that connects the top of the carseat to an anchor mounted in the vehicle at a location behind the carseat, usually the parcel shelf or a point on the floor of the cargo area. It is designed to prevent the forward movement of the top of a forward-facing carseat in a frontal crash. This reduces the head excursion of the child, and can reduce the chances of injury. Almost all current carseats can only meet the tougher new federal safety standards when the tether is used, even though they must still meet the minimum safety standards without a tether.
To install a top tether, you need both a carseat with a tether, and a vehicle with an anchor. All convertible and forward-facing carseats come with tethers. Most model year 2000 vehicles have tether anchors installed at the factory. Virtually all model year 2001 and later vehicles have tether anchors as well. Vehicle owner’s manuals often detail the locations of these anchors. They can be on the bottom of a seat, in the floor, on the rear deck of a sedan/coupe, in the cargo area roof of a wagon or SUV, and may even route through a fabric loop in some pickup trucks. In some cases, the carseat’s owner’s manual may also specify other anchor points that can be used for a tether. In a few cases, the manual may also specify the orientation that the hook must use when attached to the anchor.
Most older vehicles made since 1989 have factory locations for the installation of a tether anchor. Some older vehicles can also have an anchor installed by the dealer. Installation can vary in difficulty. An owner can usually buy a tether anchor part kit from a dealer parts department. Other vehicles may require some drilling or other customization, and this should follow industry recommendations. Ford, GM, Chrysler and other makers have programs for free tether anchor installation at participating dealers.
The adjustments for tether strap lengths also vary from carseat to carseat. Some are easy to change, with just a tilt or push of a button. Others require fiddling with more complicated slider buckles. The end result should be the same. Once the tether is tight, the top of the carseat will be restrained from forward movement.
Top tethers MUST NOT be used with rear-facing infant or convertible seats, unless it is SPECIFICALLY mentioned in the owner’s manual. At this time, there are only a few seats available in the USA that can be tethered in rear-facing operation. These include convertible seats from Britax, Combi and Diono. Some of these models allow for a rear-facing tether that can be anchored toward the front of the vehicle (TFV or “Swedish Method”), or toward the rear of the vehicle (TRV or “Australian Method”). If specified in the instructions, either method is acceptable provided a suitable anchor is available. The TRV method may improve safety in a frontal crash. The TFV method will improve stability and will help attain the appropriate recline for newborns and young infants. It may also improve safety in side, rear and rollover crashes, as it can limit the rebound of the carseat. Studies in Sweden show very low fatality rates, partially due to the fact that they keep their children rear-facing until age 3 or 4, and tether rear-facing seats in this manner. Rear-Facing is Safest for children and the American Academy of Pediatrics
recommends rear-facing as long as possible.
If you have a tether on your carseat and an anchor in your vehicle, this system is recommended to reduce the chance (and severity) of injuries in a crash. Please consult the owner’s manual for your carseat and your vehicle for details. You can also contact the manufacturer of your carseat and vehicle for this information. Some auto dealers will also be able to help. The website below has additional information:
NHTSA LATCH and Top Tether Information
LATCH stands for Lower Anchors and Tethers for CHildren. LATCH includes two lower anchor attachments AND a top tether. The term is often used generically to refer only to the pair of fixed lower anchors built into the bight or crack between the seat back and seat cushion. These anchors are specifically designed for carseat installation. When used, seatbelts are no longer necessary to install the carseat. The idea is to make it easier to install carseats safely, and to make it more universal among carseats and vehicles. LATCH will be found on infant seat bases, rear-facing, front-facing and combination booster seats that have an internal harness. Carbeds, infant seat carriers, booster-only models and vests are exempt and may not have LATCH.
The LATCH system was originally called ISOFIX, a term still used in Europe. In Canada, it is the Lower Universal Anchorage System (LUAS) or CANFIX. It has also been called the Universal Child Safety Seat System or UCSSS. Some carseat companies have trade names for this system, for example, Britax uses the term ISOFIT All of these names refer to the same universal anchorages that appear on a few model year 2000 vehicles and even more model year 2001 and 2002 vehicles. These are required by law in the USA for almost all model year 2003 and later vehicles. With the exception of the Volkswagen Passat and a few Audi models since 1999, lower LATCH anchors cannot be retrofitted onto earlier model vehicles.
LATCH is not necessarily safer than using a seatbelt to install a carseat. A carseat installed properly with seatbelts should be just as safe as one using LATCH. The advantage of the LATCH system is that it should make it much easier to get a proper installation. In a vehicle that does not have LATCH anchors, a carseat with LATCH capability can also be used with the vehicle’s seatbelt system instead of LATCH. If your carseat and vehicle are LATCH equipped, it is recommended that you use the LATCH system if it results in a good fit for the carseat. It is still possible that some combinations of LATCH carseats and vehicles will not work well together, and in that case it is preferable to use the seatbelt for installation if it is more secure. It is not necessary to use both the seatbelt and the LATCH system. With some vehicles and carseats, the manuals may specifically instruct NOT to use both systems. More information about LATCH use can be found at these websites:
- Consult your owner’s manuals to identify the correct attachments to use and the location of the anchors. Make sure the LATCH attachment straps are loose.
- Start with the carseat sideways on the vehicle seat. A front-facing seat with its back toward you, or a rear-facing seat with the front toward you. Attach the farthest attachment to the far anchor, put the seat into position, then attach the nearest attachment to the near anchor.
- Push-in type connectors and rigid LATCH seats should give a positive “click” when attached correctly.
- Connectors with a hook must be carefully inserted over the anchor, then pressed down before pulling back and tightening. Alternately, you may insert the hook sideways and rotate it downward before pressing it onto the bar.
- Verify again that you are using the correct anchors for rear-/forward-facing use, that the anchors are in the correct orientation, and that the anchors are firmly attached to the bar and not the upholstery.
- Press the carseat firmly down into the vehicle seat while tightening the straps. If your carseat has two straps, press down on each side while you pull the strap(s) tight.
- For forward-facing seats, attach the top tether to the appropriate anchor and tighten the strap.
- It may be difficult to remove the LATCH connectors from a tight installation. Loosen the straps by pressing the seat into the cushion, then tilting the adjuster to loosen the straps. With hook type connectors, you must depress the tongue, push the hook over the bar then rotate 90 degrees before pulling the hook free.
- Rigid LATCH seats are easier. Usually they only require extending the rigid attachments, locating the anchors then pushing the carseat firmly into the back of the vehicle seat. A push or squeeze of a button is all that is needed to release the seat.
- LATCH lower attachments are now found on most carseats that have an internal harness. On an infant seat, the lower attachments will be found on the base. Though not required, a manufacturer may include LATCH on the carrier of an infant seat as well. Infant seats will not include a top tether. Convertible seats can use lower LATCH anchors for either rear-facing or forward-facing installations. Some convertible models may include separate attachments for rear and front-facing use, so it may be important to make sure you are using the correct lower attachments. Other convertible models may require the parent to adjust the lower attachments in some manner when switching from rear-facing to forward-facing operation. For these, it will be important to read the manual to make sure that you have routed the lower attachments correctly and are using the connector correctly (some connectors must be used in a particular orientation if specified in the manual). As mentioned in the section on tethers, most convertible models may NOT use a top tether while rear-facing.
Carseats that may only be used forward-facing will usually have the most straightforward LATCH installation, with only one set of lower attachments. Combination models that have an internal harness and convert to a booster will also have LATCH. Most manufacturers will only allow the use of the lower attachments and top tether when the combination seat is used with the internal harness. If the harness has a 40 pound limit, it is removed and the combination seat is used as a belt positioning booster. If the harness has a weight limit higher than 40 pounds, then the seatbelt should be used to install the seat once the child exceeds the seat’s LATCH limit. When used as a booster, most manufacturers will NOT allow the seat to be attached to the vehicle with either the lower anchors or the top tether. There are exceptions to this. The Britax Frontier and some Graco and Evenflo models are exceptions to this rule and allow top tether or lower anchors to be used with their combination boosters, both with the harness and as a belt positioning booster . You MUST read your owners manual to find out what is recommended regarding LATCH and tether use with a combination booster model. Most models that only function as a booster will not have LATCH at all, though there are exceptions, such as the Britax Parkway SGL and the Diono Monterey.
There is growing interest in using the top tether and lower anchors for children in harnessed forward-facing carseats that have weight limits above 40 pounds. The government safety standards do have a safety margin above that, and were based on a combined child and carseat weight of 65 pounds. It is possible that some automakers added a safety margin above that. Even so, it is best to check with your vehicle’s manufacturer and carseat manufacturer if this is an issue, especially if your child exceeds 48 pounds. Unfortunately, some companies may not have this information readily available for consumers.
(Diono does allow consumers to use the specialized LATCH attachments up to the full weight capacity of the Radian carseats if the vehicle was manufactured after Sept. 1, 2005. More information is available at the Car Seat Blog.
Using LATCH in the Center Position of a Rear Seat
One other important issue is the use of the LATCH lower anchors to install a carseat in the center position. In general, the center is the safest position for a carseat as long as it can be installed properly there. Unfortunately, few vehicles have a separate pair of lower anchors specifically for the center position. A few other vehicles may designate that the center position can be used for LATCH because the spacing between the innermost anchors still meets the standard (about 11 inches or 280mm center-to-center). Here is a general set of best practice guidelines to determine if you can install a LATCH carseat in the center of the rear seat, using the “inner” LATCH anchors from the outboard seating positions:
- If either the carseat or vehicle owner’s manual prohibits the use of the center position for this type of installation, you should use the seatbelt for installation if appropriate.
- If both the vehicle and carseat owner’s manuals allow the use of the center position using the “inner” bars from the outboard positions, then you may try install the LATCH seat this way if it fits properly.
- You should not attempt this if the center is not an actual seating position, if there is no top tether anchor available for the center, or if the manual otherwise prohibits any carseat placement in the center. Use the outboard seating positions instead.
- Do not attach lower attachments from two child restraints to the same lower anchor!
- If you are unsure because there is conflicting or insufficient information, then err to the side of caution and DO NOT try this type of installation. LATCH is not necessarily safer than using the seatbelts. If your carseat fits well in the center using the seatbelts, then that is still the safest option in most cases.
Note that carseats with rigid anchors must only be installed in designated LATCH positions with the standard spacing. There is a gray area with center placement when one manual approves the use of the center position even if the spacing is wider than the standard, but the other manual has no recommendation. There is not yet enough data to determine if the significant danger of placement in the outboard position (closer to a side impact) is enough to balance the unknown risk of using LATCH anchors with spacing wider than the standard in the center. As with the many other confusing issues on child safety seat installation, you should always check your owner’s manuals first. In some cases, the manufacturer’s customer service departments may also be able to help. Finally, you can ask a trained child passenger safety technician on our forums or find one for a free carseat inspection in your area.
Most current LATCH models in the USA use a flexible belt to attach the carseat to the anchors. There is also a rigid attachment system that tends to be extremely easy to use. The only harnessed rigid LATCH model recently on the market is the Clek Foonf convertible, with rigid LATCH connectors on the base that make forward-facing LATCH installation particularly quick and easy. Belt-positioning boosters are beginning to utilize rigid LATCH for added stability and protection, such as the Kiddy Cruiserfix Pro. Consumers should note that, like any carseat, any particular rigid LATCH model may not work in some vehicles. The shape of the seating cushions, spacing and location of the LATCH anchors can cause issues with rigid LATCH systems. In most vehicles that do work with rigid LATCH restraints, they have been extremely simple to install in just a few seconds— literally, “click and go.” Plus, rigid LATCH seats tend to be extremely secure in frontal impacts and are proving to provide extra protection in side impacts as well.
It is worth noting that the September 2002 federal deadline applied to manufacturing only. Manufacturers continued shipping remaining inventories of their existing models until supplies were depleted. Similarly, retailers also sold existing non-LATCH models for some time past the deadline. It is possible that consumers still purchased non-LATCH models into 2005 and beyond. However, nearly all of the restraints that were produced before the mandate have expired even if they were purchased in the last few years. Consumers will have no trouble finding an appropriate LATCH-compatible model in today’s market.
Virtually all vehicles sold since 2003 have LATCH as standard equipment in at least two seating positions. Many model year 2002 vehicles and some model year 2001 vehicles have LATCH as well, including many models of minivans and SUVs. Only a few model year 2000 vehicles had LATCH, including the 2000 Ford Windstar. VW Passat and some Audi models since 1999 may be able to have the LATCH system installed by the dealer. Lower LATCH anchors cannot be retrofitted into other vehicles. The most definitive source of whether or not your vehicle has LATCH is your owner’s manual.
Summary: DOs and DON’Ts:
- Check your vehicle and carseat owner’s manuals for information about LATCH and tethers. In some models, it is even important that you attach the hook to the anchor in a particular way.
- You should always use a top tether if one is available. The top tether improves safety when you install a carseat with a seatbelt or with the lower LATCH anchors.
- Rear-facing child seats should not use a tether unless it is specifically approved in the carseat instruction manual.
- It is almost always required that you use the top tether when you are using the lower LATCH anchors with a forward-facing carseat, unless the manual for your carseat specifically states it is not needed.
- The lower LATCH anchors cannot be used to attach a top tether, and vice-versa.
- Lower LATCH anchors and top tether anchors are limited to one carseat each. You must not attach two seats to the same anchor. (Note: A few new vehicles, particularly extended cab pickups, do allow more than one tether hooked to an anchor, but this is ONLY allowed if stated in the owner’s manual for the vehicle under
- Even though it is possible, it is not recommended that you install a LATCH carseat in the center of a rear seat by using the “inner” lower anchors intended for outboard positions unless the owner’s manual states that you are allowed to do so. This recommendation may change after further testing, but at this time consult your manual for how to use your vehicle’s LATCH system.
- Typically, it is still recommended that you install a carseat in the middle position if possible. A center installation using seatbelts is preferred over an outboard installation using LATCH, provided that it fits well and that there are no other restrictions in the owner’s manuals.
- Seatbelt systems should not be used as top tether anchors, unless this is specifically mentioned in the vehicle owner’s manual and carseat instruction manual.
- It is OK for a forward-facing tether anchor to be offset from the center of the carseat. It is recommended, however, that the angle be no greater than 20 degrees from center. You may use a manufacturer’s pre-installed tether location even if it is over 20 degrees offset from center, provided it is the anchor that is recommended
for the position where your carseat is installed. Tether straps should generally be as tight as possible, and can even compress the seat fabric. It does not have to be so tight that it causes damage to fabric or seat cushions.
- If your tether or LATCH straps are not in use, stow them away securely.
- If you are using LATCH, the seat belt system is not needed. Leave the seatbelt unused. If your child can reach an unused seatbelt, it is critical that you take steps to prevent your child from grabbing hold of the belt. Children have been strangled by seat belts when they were able to wrap them around their neck and activate the switchable locking mode. If you can, route the seatbelt around the back of the vehicle seat and buckle it, activating the switchable locking feature if possible. If the car seat is forward facing and you cannot route the seat belt behind the vehicle seat, pull out enough webbing to activate the switchable retractor, buckle, and install the car seat on top of it. Do not route the seat belt through any belt path on the car seat.
- DO NOT use LATCH or tether straps made for one brand/model on a different brand/model. They may appear to work fine and look similar, but this will certainly be untested. There may also be incompatibilities which are not apparent that may cause loosening over time or failure due to improper distribution of forces in a crash.
- There is no standard for using LATCH or top tethers with combination seats that are being used as a belt-positioning booster. Some manufacturers may allow this, though most do not. When in doubt on any aspect of tether or LATCH usage, ALWAYS consult the owner’s manual of your vehicle and carseat as the best resource.
- Many harnessed carseats with LATCH are rated above 40 pounds. It is recommended that you contact your vehicle and carseat manufacturer to determine their policy on top tether and lower anchor use above 40 pounds. This information may be in the owner’s manual on some models.
LATCH and tethers are important safety advances for child safety. If you have young children and are considering a new carseat or vehicle, please investigate these options carefully. Also, please visit our Guide to Carseat Selection and Use. We would be very happy to try to answer any questions or problems you may have regarding LATCH, tethers, or carseat installation. Please post them at our FORUMS.