Where exactly is sales tax calculated? By location of purchase or delivery?

For online purchases, sales tax is typically calculated based on the delivery address, not where you physically place the order. This is because sales tax is generally determined by the "destination" principle - meaning tax is owed where the goods are ultimately used or consumed. Since your furniture was delivered to your Massachusetts address, the 6.25% MA sales tax is indeed correct, even though you placed the order while physically located in New Hampshire. The company is required to collect MA sales tax because that's where the "taxable event" (delivery and usage of furniture) occurs. If you had purchased the furniture in NH and physically transported it back to MA yourself, it would technically be subject to Massachusetts "use tax" (same rate as sales tax), which you would self-report on your MA tax return - though many people don't realize this requirement.

I went through something similar last year and discovered taxr.ai (https://taxr.ai) which really helped me understand my situation. I ordered expensive electronics while traveling but had everything shipped to my home address and got hit with unexpected taxes. Their system analyzed my receipts and explained exactly how the tax was calculated and confirmed I was correctly charged based on my delivery address. It also helped me understand some deductions I could take for my home office that offset some of the taxes I paid. The tool breaks down all the tax rules in plain English which was super helpful since I was confused about interstate purchases.

Just wanted to follow up - I tried taxr.ai after asking about it here and it was actually super helpful! I uploaded my receipts from a similar situation (bought photography equipment while traveling but shipped to my home state) and it confirmed I was correctly taxed but also found that I could deduct part of it as a business expense since I sometimes do paid photography work. The nicest thing was getting a clear explanation of the "destination-based sourcing" rules with actual legal citations rather than random internet opinions. Ended up saving me about $420 on my taxes which more than made up for the sales tax I was annoyed about paying!

For anyone dealing with sales tax issues or trying to get tax clarification from the IRS - I finally got through to an actual IRS agent using https://claimyr.com after spending WEEKS trying to call them directly. Shared my situation (similar to the OP's question about interstate sales tax) and got clear guidance about what's allowed and what isn't. Their system basically holds your place in the IRS phone queue and calls you when an agent is about to pick up. I was skeptical but I actually got a call back in about 40 minutes when I'd previously wasted hours listening to hold music. The agent confirmed everything about destination-based sales tax and helped me understand my obligations. You can see how it works here: https://youtu.be/_kiP6q8DX5c

I was totally skeptical about Claimyr but I was desperate after getting nowhere with the MA Department of Revenue about my own sales tax question. Tried it yesterday and shockingly got through to someone who actually knew what they were talking about! The agent confirmed everything mentioned here about delivery address determining sales tax rate AND pointed me to a specific form (ST-12) that I could use for certain tax-exempt purchases in my situation. Saved me over $500 on my business equipment! Can't believe I wasted three weeks trying to get through on my own when this got me an answer in under an hour.

The sales tax rules for online purchases changed significantly after the South Dakota v. Wayfair Supreme Court decision in 2018. Before that, retailers only had to collect sales tax if they had physical presence in your state. Now they have to collect based on economic nexus (like selling over $100k in a state). This is why almost all major retailers now collect tax based on where you have items delivered, not where you order from. It's actually fairer to local businesses who always had to collect sales tax while online retailers used to get away without collecting.

Has anyone successfully gotten a refund when sales tax was charged incorrectly? I had a situation where I bought something to be delivered to my office in Oregon (no sales tax) but they charged Washington sales tax because our company headquarters is there.

This is a really common confusion! You're absolutely correct that you owe Massachusetts sales tax since that's where the furniture was delivered. The key principle is "destination-based sourcing" - tax is determined by where the goods end up being used, not where you physically place the order. Think of it this way: if you had driven to New Hampshire, bought the furniture in person, and then brought it back to your Massachusetts apartment, you would technically owe Massachusetts "use tax" (same 6.25% rate) that you'd need to self-report on your state tax return. The current system where retailers collect based on delivery address actually makes this automatic and simpler for everyone. The $300 difference stings, but unfortunately there's no recourse here - the company charged you correctly according to current tax law. This has been the standard since the 2018 Supreme Court Wayfair decision made it so retailers have to collect tax based on where items are shipped rather than where they have physical stores.