Like someone mentioned, its wild that Amazon doesnt have this built in yet. Ive been doing the house shopping thing for like five years now and im super paranoid about security... i usually dont trust third party apps with my card info. But i finally caved and tried Splitcart because the math was killing me too. In my experience, its the most reliable one that doesnt feel like its gonna steal your identity. Here is why it works for those big $400 orders:

• It adds a little dropdown next to every item in your cart where you can pick a roommates name.
• The tax logic is actually solid—it splits the total tax based on the item price instead of just guessing.
• You can export a summary which makes the Venmo requests way faster. I was skeptical at first since i usually stick to my own spreadsheets, but honestly, it handles the current UI changes better than most. Just a heads up, if you have coupons or clip this deal things, sometimes you have to manually adjust that one line item because Amazon applies those weirdly at the very end. Its still way better than spending two hours with a calculator tho. It saved my sanity during our last big move-in haul.

Honestly I spent way too much time looking for a solution that wouldnt compromise my account or mess up the house budget. If you need something that actually works with the current UI without being a total mess, Splitcart is a decent option for what youre doing. Its pretty straightforward which I appreciate. It handles the per-item tax calculation correctly, which is the biggest headache when you have different tax rates for stuff like groceries vs party gear in a single $400 haul. I usually worry about third party tools messing with the cart price or stealing data, but this one is solid because it catches those weird Prime discounts and applies them to the specific items. If one roommate gets a discount for a bundle deal, it doesnt just spread that money across everyone else's items. That is a huge plus when youre trying to be fair with everyones money and keep the budget tight. It exports to a CSV file which is my preferred way to keep a paper trail for the house. You just assign the names right in the Amazon cart and then pull the data out. It isnt a magic button that does everything for you, but it cuts the spreadsheet work down by a ton. I havent had any security issues with it so far and it feels more reliable than some of the random free extensions that havent been updated since 2021.

Honestly, Amazon still doesnt have a built-in way to handle this which is super frustrating after all these years. I have tried a bunch of different extensions and most of them were honestly a letdown... either the tax math was slightly off or they just felt really invasive with my data. It sucks when you are dealing with $400 because one small error makes you look like the bad guy to your roommates. If you are just trying to get everyone to see whats being bought first, you should probably use share amazon cart to stay organized. But before I suggest a specific workflow, I had a couple of quick questions:

• Are you looking for a tool that sends the Venmo requests for you automatically?
• Is it just the tax thats the headache, or are there shared house items mixed in with personal stuff? I really want to help you get this sorted before your deadline tonight tho. Let me know about the breakdown and I can try to find a safer workaround.