Before you start

A passport or EU/EEA ID card, shown for prepaid and sometimes for contracts
An unlocked handset, or one that supports eSIM
A Dutch IBAN for a monthly contract's direct debit
A BSN for most SIM-only contracts; handset bundles also trigger a BKR credit check

Step-by-step

1
Buy prepaid on day one and stop worrying about it
There is no SIM-registration law here, so a prepaid SIM from Albert Heijn, HEMA, a Vodafone or Odido shop or a Schiphol kiosk works within minutes with no form to fill in. Lebara is the usual newcomer choice because its packs and support are in English.
In personWho: YouSame day, about 15 minutesSIM around €5-20 plus a bundle
2
Move to a SIM-only contract once the IBAN exists
SIM-only plans are cheaper per gigabyte and most are cancellable monthly. They require a SEPA direct-debit mandate on a Dutch account and usually your BSN. This is why the phone contract sits third in the chain after registration and banking.
OnlineWho: YouSIM arrives in 1-3 working daysFrom roughly €6-8 per month
3
Use an MVNO rather than a flagship store
Simyo runs on KPN's network, hollandsnieuwe on Vodafone's, and Simpel, Ben and Lebara resell the big three. Coverage is the same physical network at a fraction of the price. The only reason to pay a carrier premium is a bundled TV or fixed-line package you actually want.
OnlineWho: YouSame day to orderTypically half or less of a carrier plan
4
Check what is actually in the building before signing a broadband contract
Ask the landlord or agent whether the flat has fibre to the door, coax from Ziggo, or only copper. Rotterdam's post-war and post-2000 stock is well served; some surviving pre-war blocks in Delfshaven and the Oude Noorden are not. Where fibre is present, symmetric gigabit is cheap by European standards.
OnlineWho: You, before signing the leaseAsk at viewingRoughly €40-60 per month; installation sometimes free on a promotion
5
Keep the number when you switch, and never cancel first
Number portability is standard and the new provider executes the transfer. Cancelling the old contract yourself before the port completes is the one way to lose the number permanently.
OnlineWho: YouA few working daysFree

Documents you’ll need

Passport or EU/EEA ID card
Dutch IBAN, for a contract's direct debit
BSN, for most SIM-only contracts
Proof of address, for a fixed-line installation

Things most newcomers don’t know

There is no SIM registration in the Netherlands, which is unusual in Europe and genuinely useful on day one.

Most European countries require an identity document to be recorded against a SIM before it activates, which for a newcomer without local paperwork can mean days of delay. Here you walk into a supermarket, pay cash, and have a working Dutch number before you have a Dutch address. It removes any pressure to sign a bad contract in your first week.

Source: community-reported

The Dutch IBAN, not the SIM, is the real gate on a cheap phone plan.

Almost every SIM-only contract bills by automatische incasso, which requires a Dutch bank account, and most providers also ask for a BSN. That puts the chain in a fixed order: address, then gemeente registration, then BSN, then bank, then contract. Trying to jump to the end is where most first-fortnight frustration in the Netherlands comes from.

Source: community-reported

A handset bundle puts you on the BKR credit register; a plain SIM-only usually does not.

Buying a phone on instalments through a mobile plan is treated as consumer credit and is registered with the Bureau Krediet Registratie. That registration is visible to mortgage lenders and can reduce how much you may borrow later. Buying the handset outright and taking a separate cheap SIM-only plan avoids it entirely and is usually cheaper anyway.

Source: BKR

Rotterdam's rebuild is why the internet is good, and the exceptions are the old bits.

A city centre reconstructed after 1940 and again during the 1990s and 2000s waterfront redevelopment has modern ducting almost everywhere, so fibre and coax coverage is high and speeds are cheap. The surviving pre-war fabric in Delfshaven, the Oude Noorden and parts of Zuid is where you can still find a flat that cannot get fibre. Ask at the viewing, not after signing.

Source: community-reported

Common mistakes to avoid

Trying to sign a SIM-only contract before you have a BSN and a Dutch IBAN, and being rejected at the direct-debit step.
Paying flagship carrier prices for exactly the same network an MVNO resells.
Taking a handset bundle and picking up a BKR credit registration that later affects a mortgage.
Assuming any Rotterdam flat can get fibre — the surviving pre-war stock sometimes cannot.
Cancelling the old contract before the number port completes and losing the number.

Some of this may be out of date. Spotted something inaccurate? Help us keep it right for the next newcomer.