Before you start

Passport with a valid Pakistani visa, or CNIC/NICOP/POC
Physical presence at an operator's own service centre — franchise shops sometimes cannot process foreigners
An unlocked handset
A local address, for fixed broadband

Step-by-step

1
Go to an operator's own service centre, not a roadside kiosk
Foreign-passport registration goes through a different NADRA verification path from the CNIC route, and small franchise outlets frequently cannot process it. Jazz, Zong, Telenor and Ufone all run flagship centres in Karachi. Going to the right place first saves a wasted afternoon.
In personWho: YouWeek 1
2
Expect a fingerprint, not just a photocopy
Biometric verification against NADRA is mandatory and happens at the counter before activation. This applies to foreign passport holders through NADRA's foreigner verification system. It is quick, and there is no anonymous prepaid market in Pakistan at all.
In personWho: You
3
Know that your SIM allowance is much smaller than a citizen's
PTA's registration framework allows Pakistani CNIC holders a substantial number of SIMs across operators. Foreign nationals are limited far more tightly — commonly cited at a couple of SIMs in total. Do not plan on a separate work line, personal line and data-only line as a matter of course; confirm your allowance at the counter.
In personWho: You
4
Buy data generously — it is cheap
Pakistani mobile data is among the least expensive anywhere. Monthly bundles that would be premium plans elsewhere cost very little, and for many residents the phone is the primary internet connection. Coverage in Karachi is good; speeds vary by district and operator.
Mobile appWho: You
5
Ask what fixed broadband the building actually has before you sign the lease
Fibre availability in Karachi is building-by-building rather than area-by-area. StormFiber, Nayatel-style operators and PTCL all have patchy footprints, and a good address is no guarantee. If your income depends on the connection, make it a condition of the lease and verify with the provider, not the agent.
OnlineWho: YouBefore signing a lease
6
Plan for outages with a battery-backed router
Karachi's power is K-Electric's and load shedding varies street by street. A UPS or battery-backed router and a well-charged phone hotspot are standard equipment in any home office here, not a contingency.
In personWho: You

Documents you’ll need

Passport with valid visa, or CNIC/NICOP/POC
Proof of Karachi address, for fixed broadband
Fingerprints, taken at the counter

Things most newcomers don’t know

Foreign nationals get a fraction of the SIM allowance Pakistani citizens do.

PTA's subscriber registration framework treats foreign passport holders separately from CNIC holders, and the number of SIMs a foreigner may hold is much lower — reported at around two in total against a substantially higher ceiling for citizens. Anyone planning separate work, personal and data lines, or buying SIMs for family members on their own passport, hits this quickly. Confirm the current figure at the operator's service centre, since PTA revises the regulations.

Source: Pakistan Telecommunication Authority

Franchise shops often cannot register a foreign passport at all.

The biometric verification path for a foreign passport runs through NADRA's foreigner verification system rather than the ordinary CNIC route, and smaller outlets are frequently not enabled for it. The staff will try, fail, and send you away without explaining why. Going directly to an operator's own flagship service centre in the first instance turns a repeated frustration into a single visit.

Source: community-reported

There is no anonymous prepaid SIM in Pakistan, and this is a hard rule.

Every SIM is biometrically bound to an identity document at activation, matched against NADRA in real time. Buying a pre-activated SIM from a stall — which people habitually do elsewhere in the region — means using a SIM registered in someone else's name, which is both unlawful and a genuine problem if anything happens on that number. Register it yourself.

Source: Pakistan Telecommunication Authority

Fibre in Karachi is a per-building fact, not a per-neighbourhood one.

Two towers on the same street can have entirely different broadband options, because provider footprints were built out building by building. The letting agent will say 'internet is available'. What you need to know is which operator has actually run fibre into that specific building and whether there is a free port. Ask for the provider's name, then confirm with the provider. For anyone working remotely this is the most consequential question in the whole lease.

Source: community-reported