they check if it's close. I travel with my mom and pack both of our things in one. Got dinged $25.00 for a suitcase I got at Goodwill.

of carry-on bags these days but, in all the 60 years I've been flying I've never had them challenge a piece of checked luggage for size. For weight, often. But not for size. I suppose if the bag is substantially (and visibly) larger than a standard suitcase they might question it but, assuming the dimensions are only 4" greater than the theoretical 'allowed' standard I wouldn't be overly concerned. If you're really worried I'd wait to check in until it's close to flight time and they're checking in lots of people. Less likely to be scrutinized then.

and I travel a lot..DCA,IAD airports are my regulars domestically...and LHR internationally

One of my bags is particularly huge, prob around the 66in...I always get comments about how its big enough to hide a body in...I always quip back - yeah, it's the ex-..... , but no-one has ever asked to measure it..

fly Delta or Virgin exclusively..

I have a couple of their backpack suitcases, may get a roller as i age. I like the quality and construction, pockets, etc.

But I have seen others get checked, though not often.

My wife and I both travel regularly both in the US and to Asia (usually separately, so between us we travel maybe 12-15 times/year since 2012). Airlines have become rigorous about weight - I once got dinged for less than half a pound over weight) - but I've never seen them question dimensions, and people travel with a lot of huge and weird shaped stuff in Asia.

If you buy the bag new, I doubt you will have any problems with dimensions. Companies would go out of business if they sold luggage sizes that routinely violated airline regulations. I can't advise spinners (4-wheelers) enough. It can be tempting to cheap out on the checked bag and get one with just two wheels, but you will regret it.

Get the brightest, ugliest, most distinctive bag you can for checking. It used to be you could tie a red ribbon around your bag for quick identification, but everybody does that now. Then it was colored tape. Now I'm seeing more and more of that. Luggage, like modern cars, all looks exactly the same. Do something to it you can quickly identify on the luggage carousel.

Finally, we try to toe the line between quality (won't fall apart) and crappiness (don't care about it getting dinged. scratched, mauled, etc). We bought a Ricardo hard-side roller about three years ago that's made maybe 20 trips and is holding up beautifully. We bought it at a Marshall's/TJ Maxx kind of store (Tuesday Morning actually) where the stuff is new but marked down because our then bag gave up the ghost. We got it at a huge mark-down and expected it to get us back to Asia before disintegrating, but the zipper is wide and good quality, the rollers are strong, the retractable handle is sturdy. It's even doing double duty as a baby gate separating our very rambunctious 40 pound doggo from our dog-adverse cat's hide-hole. If money is an issue for you, I'd recommend it. It doesn't win awards, but my experience with it ranks it as one of the best pieces I've used.

Good luck!

....carry-on must fit into that space. You might check with a travel agency regarding checked luggage.

If all they do is add a fee and it's not too onerous, just plan to pay it.

Their constantly changing regs are just heinous, imo. They make no sense.

My bags are such that I do not have problems. I often see agents measuring bags by wrapping a chain around the bag. Seems to be more of a problem with certain airlines and destinations. Low cost airlines that are charging for every bag seem particularly vigilant.

there is a wooden box.. your bag has to fit INSIDE the box

the handle extended and broke. Hey it was ten years of being dragged around airports, stuffed to the gills, tossed all over. The new ones are slightly smaller. On short runs the cabin crew will ask me if I want to check it with them no charge..Great for me not having to stuff it into a bin. They have it waiting on the jet bridge upon exit. With the hassle over lap tops I usually put mine in the carry on. My large suitcase will hold 60lbs but I am limited using a regional to 40lbs. That's the problem, your bag is too heavy. Your already losing, since you can only add 36lbs. Overseas the max wgt for First & Business Class is 70lbs.

[link:https://www.skyscanner.com/tips-and-inspiration/airline-baggage-sizes-fees-carry-checked-luggage|

But I've never had it checked like that in the times I've had to take a flight. It's been about a year since the last time I flew, though.

I can tell you that I have never, in over 35 years seen a checked bag checked for dimensional sizes here in the U.S..

They are routinely checked for weight.

If your choice of bag is approximately the same size as every other bag out there it's not going to be an issue.

If it weighs significantly more at check-in it's going to be noticed and potentially problematic.

If the ticket agent can't lift your bag from the check-in scale to the conveyor belt the chances are pretty good it will get flagged on the basis of weight, not size.