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Price and Delivery starting at:

€ 12.95 EUR 1 semana

Unlock BLU C4

Online unlock of your C4 by experienced professionals.

  • Trust, Safety and Integrity
  • Best Prices & Delivery Times
  • Guaranteed Unlock or Refund

Price and Delivery from:  € 12.95 EUR and 1 semana

Unlock in 5 minutes following these
1. Operator 2. Service 3. Summary 4. Payment

Select the original network provider to which your phone is locked

Trust, Safety and Integrity

Trust, Safety and Integrity

Over 16 years providing 7+ Million recharges, unlocks, checks and gifcards to date.

Extremely Happy Customers

Extremely Happy Customers

Over 25,000 happy reviews combined on Google and Trustpilot

Lowest Prices Guaranteed

Lowest Prices Guaranteed

Transparent upfront pricing and best price guaranteed or your money back.

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Does unlocking my BLU phone void the warranty?

Unlocking by IMEI does not void the phone’s warranty. In fact, because you are typing in a code, no cables, software downloads or hardware modifications are required. Your BLU is in safe hands with doctorSIM.

How do I know if my BLU has been reported or blacklisted?

Reports are additional security measures which prevent the phone being used properly and are not removed by unlocking the phone.

If your BLU smartphone has been reported stolen, lost or due to unpaid bills, you should contact the original operator to remove the phone from the blacklist. Once they have done that, you can unlock your BLU phone with doctorSIM without any problems.

Why should I unlock my phone with doctorSIM and not in a local store?

The unlocking method used by doctorSIM is recommended by the phone manufacturers themselves. It is legal, permanent, doesn’t void the phone’s warranty and isn’t negated by future software updates. Additionally, you don’t have to leave your phone at the store because you unlock the phone yourself. You can also contact our first-class customer support team by telephone, e-mail or chat for assistance.

Is this 100% legal?

Our method of unlocking phones by IMEI is perfectly legal. In fact, this method is the recommended method by the phone manufacturers and network providers themselves as it won’t damage the phone or void the warranty.

Can I still unlock my BLU phone if I don’t know the exact model?

Yes, you can! You don’t need to know the exact model of your BLU as our unlock code and instructions are valid for all models.

Will I be able to use my BLU smartphone on any network in the world if I unlock it?

Yes. Once unlocked by doctorSIM you’ll be able to use your BLU on any GSM network in the world as long as it has not been blacklisted due to loss, theft or unpaid bill. Our unlock method via IMEI or MEID is permanent and the phone will never relock even with software updates.

How long will it take to unlock my BLU phone?

The guaranteed delivery time will be displayed once you have selected the country and network provider. You will also be able to see the average delivery time of the last 20 unlocking requests once you have filled in the information required to process your unlock code.

Why unlock your phone with doctorSIM?



The recommended method by the phone manufacturers and network providers.



The simple, fast, safe and legal way to unlock your phone.



This method is permanent and doesn’t void your phone’s warranty.



Your phone never has to leave your side.



Continue using your phone during the unlocking process.



First-class customer support available 24 hours a day by telephone, chat and e-mail.



You will be able to use your phone with any network provider in the world.



Backed by over 5 million successful unlockings to date.