Is there the cheapest way to send SMS activation codes?

Question

SMS

For your service, you need to send so-called service messages. Once upon a time I used smsc and they had the opportunity to significantly reduce the cost of sending when using a template like "Check Code 0000". Now, as I understand it, in order to send service messages, it is necessary to additionally pay from 1000 to 2000 rubles per month to the cashier for operators (in total, somewhere around 6000 per month for the right to reduce the price of sending a message). With current volumes (approximately 1000 sms per month), this is not cost-effective, and with normal sending, the average cost is 2.5 rubles / sms.
I'm thinking of switching to sending messages through hardware (GSM whistles or sim hubs).
Share your experience: what hardware is better to use (price / quality / cli / api) whether operators will ban SIM cards if sending goes 1-3 messages per minute (text without links)
Or advise a service with reliable and prompt sending of messages with a price of up to 2 rubles .
For me, the cheaper the better, the project is actually not commercial.

Answer 1

As an option, use sending this code to telegrams or just push them. But in general, I just subscribed to hear the options

Answer 2

The cheapest option is to call from a random number and use the last 4-5 digits as a code. By the way, a call is faster than SMS. Sometimes you have to wait for SMS.

Answer 3

There is a call option. Call from a random number without establishing a connection. The client enters the number from which they called. There is definitely a determinant.

Answer 4

Google Firebase provides authorization through various channels: email, push, sms. Limit 10k per month. Try it.

Answer 5

While we use this www.smsimple.ru/price
If a signature is needed, then the average price is 2.5 rubles.
Without a signature (random number) - 0.5 rubles, which, with your volumes, will cost no more than 600 rubles per month. (but nothing prevents adding a signature at the end of a message or at the beginning))
Sending messages with a post request.

Answer 6

Is there the cheapest way to send SMS activation codes?

Voice messages or codes in the form of calls

Not quite suitable for usability, the client (we consider the option that the client is on the site from a smartphone) in the case of an incoming call, you need to go into the call history, copy the number or remember the last digits and go back to the browser

After submitting the form, the user expects a call, remembers the last few digits, then rejects the call and immediately enters the code. Well, or takes a call and listens to the code that is voiced by the robot.

spoiler

Это значительно дешевле, чем SMS:
https://smsc.ru/tariffs?t=6 - от 0.24 р (голосовое сообщение/звонок)