Text Messages Are Being Censored in Canada


  • Note taken on [2019-11-22 Fri 08:30]
    This might not be an act of censorship. There might be another explanation. I started to look at the source code and RFCs this morning to better understand. I am very short on time at the moment and I probably will continue to be short on time until after Christmas unfortunately. If you would like to help, please contact me.
  • Note taken on [2020-02-13 Thu 05:03]
  • Note taken on [2020-02-14 Fri 04:39]
    • Updated submissions with new twilio (us) to iPhone (us)
    • cleaned up the comment field

What is this about?

Yesterday, I discovered that if I send a text containing the words: secure communication, it will never arrive at the recipients text messaging client. Something is censoring text messages in Canada.

What devices and carrier services are affected?

I do not have much data on this. I only discovered this at the very end of the day yesterday. Here is what I have been able to manually verify so far:

Sender Make Receiver Make Sender Carrier Receiver Carrier censored
Android Android Koodo Koodo yes
Android iphone Koodo Bell yes
iphone Android Bell Koodo yes
iphone iphone Bell Bell yes

Exactly what is censored?

In order for the text to be censored it must contain the exact words, secure communication, anywhere within the message. It is also important that the words, secure communication, are separated by no more than a single space and are lowercase. The censorship prevents the entire message from being delivered. I have only tested this using SMS and MMS protocols and found that MMS is not affected by this particular censorship. Here are some examples:

Message Censored? Comment
secure communication True
secure communication False two spaces separating keywords
secure communication. True trailing period
Secure communication False
secure Communication False
Any Leading Text secure communication True
secure communication any trailing text True
Appended leading textsecure communication True
secure communicationappended trailing text True
securecommunication False
leadingsecure communicationtrailing True

My testing methodology was manual and far from comprehensive. Someone needs to automate a test that sends random combinations of words from various devices and carrier services to get a better picture of the nature of the censorship.

This poses some questions

At this point all I have been able to determine is that the words, secure communication, are being censored by something when sent using the SMS protocol. I do not know if the censorship is taking place on the devices themselves, the local short message service centre, or something else. I am now wondering:

  1. Who is behind the censorship?
  2. Do they have a publicly accessible disclaimer stating exactly what they are censoring and why?
  3. Is this censorship legal in Canada?
  4. What else is being censored?

Censorship in Canada affects all Canadian citizens as well as all citizens of other countries that correspond with Canadian citizens. If you are concerned by this act against our civil liberties, then consider writing your MLA and the Canadian Civil Liberties Association.

Discussed on Hacker News

I posted this article on Hacker News and started this discussion in a thread.


I copied some details in the table below. The first 3 are my own tests. Records are paired by sender then receiver. If the test was bidirectional, then I will add vice versa in the second row comment field. Blank fields were not provided by the submitter. If a message containing secure communication was received, then !Affected will be added to the first comment field, otherwise it will contain Affected. Messages have double quotes around them so that multiple messages can be distinguished from one another. If a message actually contains quotes then it will be escaped using a backslash.

There are important fields that I am massing here. Such as whether or not data and WiFi are turned on which is important in the case of iPhone. I might move this table to its own page and re-organize it.

Make OS Protocol Carrier Region Text Comment
Nexus 6P Android 8.1.0 SMS Koodo Alberta, Canada see above Affected
Nexus 6P Android 8.1.0 SMS Koodo Alberta, Canada
Nexus 6P Android 8.1.0 SMS Koodo Alberta, Canada see above Affected
iPhone iOS SMS Bell Alberta, Canada
iPhone Android 8.1.0 SMS Koodo Alberta, Canada see above Affected
iPhone iOS SMS Bell Alberta, Canada
iPhone XR iOS 13.2.3 SMS Fizz Québec, Canada “test”, “secure communication” “test” Affected
LG G7 Android SMS Koodo Québec, Canada “test”, “test”
SMS Telus Alberta, Canada “secure communication”, “secure communication does not work” Affected, vice versa
SMS & VOIP voip.ms
Samsung S10 Android SMS Virgin Mobile Quebec, Canada !Affected
Smsung A8 Android SMS Vidéotron Quebec, Canada
iPhone 7 SMS Bell Ontario, Canada “secure communication” Affected
Pixel 3 Android SMS Koodo Ontario, Canada
iPhone iOS SMS Public Mobile “secure communication” Affected
iPhone iOS SMS Rogers vice versa
SMS Freedom Mobile Ontario, Canada !Affected
SMS Freedom Mobile Ontario, Canada
Twilio API SMS Twilio US “secure communication” !Affected
iPhone SE iOS SMS Verizon (MVNO) US “secure communication”


Your comment has been submitted and is now pending moderation

With permission, I am able to share some anonymous details regarding a correspondent’s experience trying to share a URL to a website that was hosting a collection of videos by Ty and Charlene on vaccines. I have been able to send text (SMS, MMS) containing the links mentioned below, therefore I cannot corroborate my correspondent’s claim. If that changes, I will post an update.

Do not be offended by those that challenge your world view. Instead, be offended by those with intent to suppress that challenge.

– The following has been slightly redacted / modified to protect the identity of my correspondent. –

Hi trevor, Yes both phones were android My phone is a J7 Refine Samsung android version 9.0 Pie My friends phone is a samsung A20 android 9.0 Pie also. My carrier is boost mobile which is basically Sprint and my friends carrier is tmobile. We both reside in [REDACTED].

The link which was censored was the following:


It’s a link for the videos done by Ty and Charlene on vaccines.

I also tried to send to about 8 other people that same day and no one received. (Every time i sent, my phone showed the sent message of the link twice in my texting app, if i remember correctly, and that’s what still happens usually when something is blocked). So that would have been a mixture of androids and iphones. The above censored text was only sent from my phone. The following day, i tried to send it to my boss while in the same room. I sent a text preceding the censored link and said that the link was coming, then i sent the link, and then sent a follow up text. I looked at my boss’s Windows 10 phone. It received the preceding text and follow up text but not the link. I then put a space [in the link] between the word vaccine and resent and then it went thru. That is the same test i did with my friend above. Exact same thing happened. The same day my friend had a different link for the same vaccine videos, but the link did not have the word vaccine like mine did. We only tested it from my friend’s phone to mine. I did not try sending it back. Here is the link:


My friend followed the same testing procedure as I just described and I did not get the link, but always got the preceding and followup text. But when she put a space somewhere in the link, it came thru to my phone. So we gathered that the vaccine vids where being censored. It makes sense because the documentary is very damaging to the drug and vaccine companies.

A while after that, probably about a month, tmobile went down all over the US and they suggested using Messenger or Signal to talk with people who had tmobile phones. So i got the signal app and learned it was an encryption app. So i had an idea to see if it would encrypt the blocked link. I first made sure the blocked link was still being censored by using the above test and using my standard messaging app. It was still censored. Then my friend and I both installed signal and made it the default messaging app. I texted the link and it did go thru! So by that we gathered that they were for sure censoring that link.

Yes of course u can use the information anonymously.

Trevor Wilson

Hello OldFart,

I am able to send both of the URLs that you mentioned via SMS between two phones on my personal plan. I will test between different carrier services and regions over the next week.

  • Which protocols are affected?
  • Did you keep track of which carriers, regions and devices are affected and which are not?
  • May you please share any facts you have collected? (Feel free to email me using my public key)

By the way, you are not the only person that has been contacting me about URLs that cannot be sent by SMS. With permission, I will include a portion of my correspondence in my next post to this comment section.

On a side note, I do not believe that the text “secure communication” (referring to the blog post) is being censored. I am still investigating other possible explanations.

Trevor Wilson

I noticed that messages containing my domain name are not being sent/received by Iphone users.

I had to show them screenshots to proove i sent urls or email addresses.

Try with zeroserieux.com or shared.zeroserieux.com