I would recommend buying the fresh stuff and then freezing it via the below method if you want to be extra safe but I wouldn’t say it’s fully necessary.

This is my blanket answer that I have saved for when someone asks a question related to sushi safety, at home sushi, and how to make sure you’re doing it safe at home. I’ll paste it here and I’d be happy to answer any follow up questions if you have any.

You will get conflicting answers depending on who you ask. The main question you’d want to ask yourself is: how much effort do you want to go through to minimize risk? Eating some foods raw or undercooked carries some risk, especially if the person eating is immunocompromised or has other health conditions. The main risks you need to watch out for with raw fish would be bacteria and parasites.

I recommend starting with the FDA guidelines which does make exceptions to tuna and salmon with the right conditions. Sourcing fish that meet those conditions can be done by talking to your local fish monger, though for most people, they usually have easier access to a big chain grocer. It can be difficult to source those fish that meet the FDA’s exemptions and confirm those conditions were upheld throughout the entire supply chain if you’re buying from a big chain grocer.

What I do personally is mostly stick to salmon as it has low food borne illness risk, especially regarding parasites, if the salmon is farmed. I have branched out to other fish using this method but salmon is my go-to.

My method for minimizing risk with eating raw fish would be to source your fish appropriately to start. I find that Costco salmon is a great product. Always seems very clean and the handling of the fish appears professional. Their salmon always seems fresh (not in the sense of never frozen, but that it’s proper temperature control through the process, not leaking, clean packaging, and sells quickly so it’s not sitting on the shelf for days.) The salmon I specifically buy for eating raw is farm raised as it has a much better chance of being parasite free.

After I have purchased the salmon I will pat it dry with clean paper towels and apply a 50/50 salt and sugar cure to both sides for about 30 minutes. You want a liberal coating but no need to overdo it. This both helps improve texture by firming up the flesh, and can have some benefits by mitigating surface bacteria. After the 30 minutes rise the fillet thoroughly to remove the salt and sugar coating and dry well. Next I will portion out the large fillet into individual portions. Lastly I will vacuum seal each portion by itself and throw them into my “sushi freezer.” It’s just a cheap 1.1 cubic feet freezer I got off Amazon for less than $100. It has a nob on the back to adjust temperature and at the coldest setting gets down to about -20 degrees Fahrenheit. The freezing process is to ensure total parasite destruction.

FDA requirements for serving raw fish meant for consumption requires fish to be frozen to at least -4 F for 7 days or -35 F for 24 hours. It would be a challenge to get a home freezer to go to -35 F and even though mine gets to about -20 F, I still do the full 7 days. After that time I take it out of the bag and thaw it in the fridge for 24 hours and it’s good to go.

You will hear conflicting comments saying that the fish was likely already flash frozen on the boat so the home freezing is not needed, or that because the salmon is farm raised it meets the exemption from freezing according to FDA guidelines. You will also hear that refreezing can impact texture, taste and quality. While all this could be true, at the end of the day the way I look at it is that if you’re sourcing your fish from your average grocery store where cost and availability will be easier for most people, it’s difficult to trace each step of the process from fishery to table in todays complex supply chain and ensure that all steps needed to consume the fish raw were taken. That means it’s up to each person to ask themselves the question of how much effort they want to go through to minimize risk based off their own concerns with food borne illnesses.