Just realized a lot of people don't really think about this when they're selling stocks, but the method you choose actually matters way more than most investors realize for your taxes.

So here's the thing. When you decide to sell some shares you own, you've got options on which specific shares to actually sell. The two main approaches are FIFO and LIFO, and honestly, picking between them can swing your tax bill pretty significantly.

FIFO is first in first out - meaning you're selling the shares you bought earliest. LIFO is last in first out - you're selling your most recent purchases instead. Sounds simple enough, but the tax implications are where it gets interesting.

If you don't tell your broker which method you want, they'll automatically default you to FIFO. That's the IRS standard. The upside of FIFO is that your older shares have usually been held longer, so you'll typically qualify for long-term capital gains rates, which are way more favorable. The downside though? Because stock prices generally go up over time, those early shares you bought are sitting at a lower cost basis. That means when you sell them, your taxable profit ends up being bigger than if you'd sold something you bought more recently.

LIFO is the opposite play. You have to actually request this from your broker - they won't do it automatically. The benefit here is that the shares you bought most recently tend to have less profit baked in, so you can make a sale without getting hit with a massive tax bill. But here's the catch - because these are newer shares, if there is a gain, it might get taxed at the higher short-term capital gains rate instead of long-term rates.

The key thing with either approach is making sure you get written confirmation from your broker that they're using the method you actually selected. If you don't have that documentation and something comes up later, the IRS could just assume you never made an election and force you into FIFO anyway.

People who are serious about maximizing their returns after taxes really need to think about this stuff. It's one of those decisions where being intentional about whether you're using FIFO or last in first out stock selling strategy can genuinely keep more money in your pocket. Most people just let it happen on autopilot and leave money on the table.