Which business bank should I switch to?

I'm getting really annoyed with Starling Bank. They've had quite poor customer service for a while now - outsourced to cheap labour abroad. 
I've been with them for two years and initially they were super!

What should I use instead? 

Where are you and what features are you looking for? I use Wise and Revolut for international (non-US) transactions. I use Hello Bonsai for US-based clients. (They're a payment processor, but they have a debit card for easy access.) I also have Found, which is a bank specifically for founders.

Oh also useful info: Are you opening an account for yourself or business? I've got some good suggestions if it's the latter.

My business, UK based business but as the director of the company, I'd like to keep an open mind towards remaining in the UK and moving good if they allow UK business accounts even if you live abroad.

I'm definitely not an expert, but I've worked with a handful of UK clients over the last decade. When I got TransferWise (now Wise), getting paid by international clients was way simpler (and cheaper), so that might be something to keep in mind if you're doing business with non-UK residents.

Revolut has made it really easy for me to transfer money into a UK-based bank account so I can access it when I travel. Definitely look it up to make sure it meets your criteria, though.

This might make it unsuitable:

"Unlike traditional banks, Revolut's deposit protection is limited. Although savings in a Revolut account are protected up to a specific amount, they are not covered by government-backed deposit insurance programmes. This may be of concern to those looking for increased deposit security."

PS Not me being the absolute worst and not realizing you literally said it's for your business in your question. In my defense, I'm usually on here at like 2am, so my brain isn't always all the way there lol 🫠

As you are based in the UK you might be able to use
I really like them and have been using them for a few years. They seem to be dev focused with APIs and very logical approaches to a few features. Every transfer is real-time, you can use a real credit card like a debit card, and use 20+ sub-accounts for budgeting.
They can be shared with friends as well. Cards can be re-mapped to different accounts just seconds before the transaction.
They are not perfect, but exactly what I need.

The question is, what are your requirements, needs, and pet peaves when it comes to banks?

They don't seem to be regulated, so no money back guarantee from the government.

Nice! Are you with them?

Yes, I said so in my first reply ;)
I have 1 account as an inbox, 1 for fixed costs, 2 for saving, 3 for my flat share, 1 for my business and one to share with my digital nomad friends.
1 physical card and 5 digital ones.

US specific recommendations for completely free business banks with no fees or minimum balances:
- Mercury
- Novo
- Brex (use when you're further along and need expense tracking functionality for your employees, but they also have a bank account built in)

Mercury's customer support is slightly better in my experience but I use Novo for most everything because they have a unique benefit where they offer faster payouts from Stripe than anyone else.

Novo also has invoicing software built into the bank powered by Stripe which I've used to bill consulting clients a couple times.

I'd love to use Mercury but my business is registered in the UK.

Should I maybe register it in Singapore?

Definitely don't ask me for legal advice haha. That said, I'd probably only consider moving to Singapore if you're doing a certain level of revenue, otherwise it's probably not worth the hassle to save X% in tax

Not moving, just reregistering the business there...

Would still be tax resident in the UK.

Yeah I have no idea about UK tax law, consult a CPA - but typically you will be taxed in the place that you live (unless you are a US citizen, then they tax you globally no matter where you are), not where your business is registered, so may not be worth it unless you're willing to move to SG

Banks everywhere are a pain to deal with. Your best path forward might be to accept this and pay someone (accountant, etc) to deal with your bank instead of you.

The best of all our advice. CPAs are worth their weight in gold.

This, seriously is the best advice - accountants have saved me from endless anxiety and admin.