Don't have a solution but observe the follow crash sequence and work around sequence for me.

2020 TurboTax Deluxe build 2020.r14.034 (2/3/2021 build date)

macOS Big Sur 11.2 on 2015 Macbook Pro 13"

Seems like the latest TTax and macOS version

1. Had 2 returns open and just crashed.

2. Launch post crash will trigger a window to send report to TTax. Window heading "It looks like we hit a snag"

3. Sent a report

4. Next launch briefly flash update window and crashes

5. Go through complete uninstallation + reinstall sequence for macOS per this link

       Remove and reinstall TurboTax for Mac (intuit.com)

6. Launch Turbotax, install all updates, get the send crash info to TTax screen "It looks like we hit a snag" If you send a report, next launch will be crash again and back at step 4.

7. Only work around is to never send a report and just kill the "It looks like we hit a snag" popup window. then TTax will work. Downside is having to kill this send report window on every launch.

This launch crash seems to require cleanup of every Turbotax installation on the computer. I fixed my 2020 install with above procedure. But 2019 still crashes at launch and probably require same full uninstall+reinstall+kill send crash report window steps.

Hope TTax gets this, I obviously can't send them a crash report haha.

UPDATE : When to quit the crash report window seems to matter. If quit too early, future launches will startup with multiple crash report windows. Best time to quick this windows seems to be after all the software is updated after a reinstallation and turbotax is just waiting for user's input (opening a return or do something on the return that is opened)

I'm also having this problem, starting late last night and today.  Running Big Sur 11.2 on a MacBook that's a few years old. TurboTax 2020 for Mac was working, I just got everything in, but now it's gone bye bye. I tried deleting the app and reinstalling it. Then, after checking other comments, I tried opening TurboTax 2019. It said it needed updates applied. Now it, too, also doesn't open. A small little notice pops up and disappears before I read it, but the app won't launch.

ditto, my issue also started late last night so perhaps latest update triggered this error. Able to getting running now with the above posted sequence for now. Just have to live with annoying crash feedback window on every launch.

Please contact our customer service. Follow the instructions in this TurboTax FAQ to contact Customer Support to obtain a contact number:

https://ttlc.intuit.com/replies/3300041

Same issue with Deluxe 2020 and 2019

TT agent suggested from Finder use GO tab at top then GO To Folder ~/library then PREFERENCES then delete file 

com.intuit.turbotax.2020.plist 

I deleted and reinstalled TT Deluxe 2020.and installed update. I disregarded the error message because I didn't see any error info. I opened and closed TT several times but it started crashing again and repeated the delete, reinstall and update process. TT seems normal except for error message.

Did anyone have this problem before updating to Big Sur 11.2?

Yes, problem started after I updated to 11.2, been doing taxes for a few days, had no issue before 11.2

Thanks, I talked to TT agent this morning and suggested that issue developed after update to 11.2. Of course I had already deleted a com.....plist fie and reinstalled TT and program is working normally.  Previously, I had  deleted the file and reinstalled TT and TT worked normally for a few hours. Even 2019 was working normally and nothing was done to correct the problem. We agreed that I would call when the problem reappeared.

I wound up spending 2 1/2 hours with a wonderful woman from TurboTax support. I’d tried the uninstall, but couldn’t find the TurboTax extensions mentioned in the article on how to fix. I’d been entering /Library in the Finder window, not ~/Library. It turns out that the “~” was really important to finding those files and deleting them. Now my TurboTax 2020 works on Mac Big Sur 11.2, thank goodness. But like other posters have noted, I still get the “error - report this to TurboTax” pop up - now I know to decline and not hit “send to TurboTax”, and I can use the application without further problems.

As long as I uncheck send automatically and not send to TT, TT20 works fine .. smells like a problem

I've used TurboTax for mac for years. This year's product however, crashes consistently. At first I could put up with it, as it just crashed when I tried to download the transactions from my brokerage accounts... However, now I'm currently not able to even open the product. I've uninstalled and reinstalled, followed the help articles on the TurboTax support site to completely remove the product from my mac, deleting all the ~/Library files, every one...  which didn't work... And then even waiting on hold an hour to speak with support. Support tells me that it's a known issue, and that they can't send me a new download, since I purchased from amazon, and the fix is to purchase a hard wired ethernet adapter to manually connect my macbook to a wired network. The project just attempts to download updates and then crashes every time. I've even updated my macbook to Big Sur as some articles said that this might help, but it didn't. IDon't waste your time...

I had the same problem --  Specifically: unable to open TTPremier 2020 and/or 2019 on Mac OS Big Sur.  The two steps recommended above by jwhaskell1 and audge66 seem to have finally resolved the problem (at least thus far):

1)" from Finder use GO tab at top then GO To Folder ~/library then PREFERENCES then delete the file named "com.intuit.turbotax.2020.plist" and 

2) launch TT2020 but disregard Intuit's error message (i.e. close the box without sending Intuit a crash report!)

I repeated the same steps for TT2019 (i.e., deleting "com.intuit.turbotax.2019.plist"

With those two steps I am finally able to run both editions of TT.  Thank goodness!

Ugh...... I went into TT this am to finalize my return and check the number. I just ran into this bug as well.

In all due respect Intuit, your QC is really bad. Between the OID bug last year, and this years plethora of bugs, I'm going to be looking for an alternative.

This is ridiculous.... first that absurd mortgage interest/refi bug, and now this. How do I get a deep discount on some seriously flawed software. 

You have lost my trust...... completely

BTW, I am not kidding.

To help get you connected to the right person for assistance, please click the link below. 

What is the TurboTax phone number?

I've had this problem repeatedly with TT Deluxe, and all since updating to Big Sur 11.2.2