Utilize your financial knowledge, give your answer or opinion to the input question or subject . Answer format is not limited.

Using multiple bank accounts
I live near historic Concord, Massachusetts, and frequently drive past Walden Pond. I'm reminded of Henry David Thoreau's words,  "Simplify, simplify, simplify." In my opinion, fewer is better. 2 checkbooks? I don't see how that makes budgeting any easier. The normal set of expenses are easily kept as one bucket, one account.  The savings 2&3 accounts can also be combined and tracked if you really want to think of them as separate accounts.  Now, when you talk about 'Retirement' that can be in tax-wise retirement accounts, e.g. 401(k), IRA, etc. or post tax regular brokerage accounts. In our situation, the Schwab non-retirement account was able to handle emergency (as money market funds) along with vacation/rainy day, etc, in CDs of different maturities. As an old person, I remember CDs at 10% or higher, so leaving money in lower interest accounts wasn't good. Cash would go to CDs at 1-5 year maturities to maximize interest, but keep money maturing every 6-9 months.  Even with the goal of simplifying, my wife and I each have a 401(k), an IRA, and a Roth IRA, I also have an inherited Roth, and I manage my teen's Roth and brokerage accounts. That's 9 accounts right there. No way to reduce it.  To wrap it up, I'd go back to the first 4 you listed, and use the #4 checking attached to the broker account to be the emergency fund. Now you're at 3. Any higher granularity can be done with a spreadsheet.  Think of it this way - the day you see the house you love, will you not be so willing to give up that year's vacation?