How do you maintain your personal financial account #s and passwords?

For something like this, I vote for simplicity. Nothing beats a list of accounts and passwords in a sealed envelope in a safe deposit box that you both have access to. It is important that both of your names are on the box to ensure that either of you can access it if something happens to the other. Being related is not enough for the bank. Not as the only place these thing exist, of course (the basic idea that @Paul laid out is similar to what I do), but as an ultimate fallback if the others fail. It also would be a good place to store the password that unlocks the electronic version of the rest.

This is also a good spot for the other things that might be needed if something unfortunate happens: wills, life insurance policies, health care directives, etc.

I have had a lot of success with a tool called LastPass. It's a free tool that you can install as an add-in to your browser. It can be opened with a password and can store all of your usernames and passwords for you in an encrypted data store in the cloud.

To address your list specifically:

• Durability against monsters, earthquakes, etc.
  • Cloud-based storage makes it durable from the perspective of your home. See here for more about availability.
• Ease of access for her
  • Can be opened with a single password (I use a very complicated one).
• Ability to progressively update it going forward
  • Yes - update it anywhere - in your browser, on the web
• Security, security, security
  • Yes - best to see here
• Ease of updating for either of us
  • Update from any computer and the updates replicate across all installations
• Ideally platform agnostic, but we're mostly Mac and iOS in the house.
  • Yes - I use mine on Windows and Linux. Mac is supported too.
• Can't easily be opened if our computers or iOS devices are stolen
  • Anything on your computer is stored in an encrypted format. It can only be opened if you have the password.

The full feature set is here. I like the password generation feature. Also, each username/password pair also allows you to attach other data like account numbers. There is also a "Notes" feature that permits storage of information not attached to a login.

I use 1Password , it also syncs you encrypted password collection on dropbox. I hear there are competitors that may be innovating faster in this field. But my key takeaways are that

1) I don't actually know very many of my passwords anymore. I just autogenerate one for each new account, and save it. The program autofills them or lets me copy and paste them when I get to a login page.

2) My mobile phone has access to these passwords too, in case I need to log in to a service on a different computer.

I like lastpass for keeping live passwords. I also keep my credit card numbers there. But the original question was about after-mortal-coil access, with which LastPass doesn't help. I have a free account at SecureSafe. They gave me a pdf with a long password which I have to my wife and sons. If they present the password to SecureSafe, SecureSafe tries to contact me by email and SMS messaging for 8 days. If they can't contact me, they release the saved passwords at SecureSafe. I have saved only the one password to my LastPass account, and that opens up everything. One could be more sophisticated, but I am an engineer of little brain and affect. (The 8 days is programmable.) This seemed like the simplest way to solve the problem.

I have no real secrets anyway, so for me it's not a very difficult dilemma.

Through years I've found following solution to be the best for me. I use free and open-source program KeePass - this is kind of interface for dealing with your encrypted data. It generates single encrypted (AES, twofish) file with all data - accounts, photos, infos, etc. And I keep this file + program on my OneDrive cloud with auto Dropbox sync. KeePass is available for any device (iOS, linux, win..). I suppose it's very handy and most secure.

You have only three options, none of which is absolutely secure:

o memory

o computer

o paper

Memory works for you, but not everyone has your memory, and you may lose it temporarily as a result of, say, a concussion. Moreover, memory works for multiple passwords only if the passwords are used frequently. So you will need the computer or paper.

Other answers have dealt with the computer option, and I have nothing to add to what they said. About paper, however, I do. And, I just realized, what I suggest will add a layer of security for the computer.

I like and upvoted the safe deposit box answer, but it is perhaps harder to access than you or your wife would like. Even if the bank is nearby, what does she do if she needs a password after the bank is closed?

I suggest a list on paper, which you keep in a fat folder full of unrelated stuff in one of your more crowded filing cabinet drawers. Make the burglars take a lot of time to find it! If you don't like the risk of a clear list on paper in the house, make up a coded list.

By a coded list, I mean, first, using a code for the name of the account. The code should be obvious to you and your wife, but opaque to anyone else. If you keep an account in a bank named, say, Wells Fargo, code it Sumner. Your average burglar is unlikely to make the connection. Or, to be even more opaque, Franklin.

That is for the account name. For the password, do something similar. If your password is, say, Sagar29,002 (the altitude of Everest in feet), code it as Jon for Jon Krakauer, the author of a classic book on Everest.

This strategy won't work if you have an awful memory, and it will be too much work to set up unless you find it fun to set up. Note that the passwords can always be found in a Google search, e.g. "What is the height of Everest?" and "What is the Sanskrit name for Everest?" All you have to remember is what clue Jon gives you.

You still need a list, in clear, in your Safe Deposit Box in case your house burns down.

Full Disclosure: We did not do a coded list. We live dangerously with a clear list in a fat folder with unrelated stuff.

Password Managers are on the rise with the growing number of digital assets owned by each individual. And the password managers make this fairly easy to regularly update it and pass them on in case of an emergency.

However, sharing your online accounts' passwords can be claimed illegal.

Which is why I prefer using a digital estate planning platform. This way, I can do more than store my passwords. I can store my digital assets, organize & manage them and even share them with my beneficiaries with different levels of access—all legally.

Personally, I use Clocr. Here, I can store all types of data with complete security. Everything is automatically encrypted (256-bit encryption) and they use a patent-pending "Shard Security."

My 2 cents on the password question:

Here are my ways.

1. I have an encrypted USB and keep my stuff there - passwords, websites, account numbers, support phone numbers, history of who I talked to, etc. I make a backup copy every month to another USB and store that offsite. I take it out, for example, to access an insurance website URL and then log in/or call support. It's all at my fingertips. Just remember the encrypted password and put the USB under lock-n-key when done.
2. Some common password prefix and different suffixes (based on good password rules) for each account/website based on something I can remember. So if I lost that USB in a fire I could reasonably guess my passwords.

Another idea is to use a main password you remember and that generates the others. I've never used it, but it looks interesting.

Look here for an example

I would NEVER put any critical document and/or password in any online solution. Google scans your content to market to you. Just how I am.

Even worse...

Why I never trust online cloud services