For tax purposes, I need to state my wallet balance on january 1st. However, I forgot to log in on that date… there have been no transactions since, but I did receive staking rewards.
What is the best way to retrieve my balance on jan-01 (or, for that matter, any other historical date), including staking rewards up to that date?
You can easily find that info by looking up your address at the:
Thanks, DevJohn. However, how can I use Cardanoscan to see the balance of my address at a specific date?
You have to do it manually by calculating all your “In transactions” and subtracting them from the “Out transactions” for a specific period of time. If you use Yoroi wallet, you can see all your transactions in one page, and it has the “Export to file” feature. You can have them in excel file and then do your calculations in an easier way.
Thanks again. Pity. I would hope that someone in the Cardano ecosystem will come up with a more user-friendly solution for this situation, which i suspect will become increasingly common.
Is there a place somewhere where I could suggest this as a request for future functionality?
There you go: Feedback - Cardano Forum
You are most welcome 
Caveat: Non-withdrawn rewards do not appear as transactions on Cardanoscan. So they will have to be substracted from the balance seperately.