"Refer four people and your year is free" is the kind of line that sounds like marketing. So here is the arithmetic, with nothing rounded in our favour.
The unit
One referral that converts to a paying customer = 3 free months of Pro, for both sides.
Pro costs $49 a year. Three months is a quarter of a year, so:
| Value | |
|---|---|
| Pro, one year | 49.00 |
| One referral, to you | 12.25 |
| One referral, to them | 12.25 |
| Referrals to cover a year | 4 |
Four referrals × 3 months = 12 months. That is where the number comes from. There is no rounding trick and no minimum spend hiding underneath it.
What it looks like as you go
| Paying referrals | Free months banked | What that means |
|---|---|---|
| 1 | 3 | Renewal moves out one quarter |
| 2 | 6 | Half a year covered |
| 3 | 9 | Three quarters covered |
| 4 | 12 | A full year, free |
| 8 | 24 | Two years, free |
| 20 | 60 | Five years, free |
The months stack. They do not expire, and they do not reset at your renewal date – your paid-through date simply moves further out each time.
The bit people get wrong
The four referrals do not have to happen in the same year.
There is no window to hit and no streak to maintain. Refer two people in March and two more the following February, and you have still earned twelve months. The counter does not reset because a year rolled over.
What matters is only that each referred company actually becomes a paying customer. Which brings us to the condition worth being clear about.
Trials do not count
A signup earns nothing. A 30-day trial earns nothing. The three months are granted when the referred company has a real recorded payment – and when you have one too.
Both sides. If you are not a paying customer yourself, the reward waits.
This is the honest limit on the arithmetic above, and it is the reason the numbers can be as generous as they are. A programme that paid on signups would pay for people who never intended to stay, and that cost would land back in the price everyone pays.
Why not a discount instead?
Because a discount decays and time does not.
Suppose the price of Pro rises in future. A percentage-based coupon is worth less every year it exists, and you would have to keep reading the small print to know what you were actually paying. Three months of Pro is three months of Pro regardless of what the price does.
It also keeps the pricing page honest. There is one price. Some customers are simply not paying it this year because they brought other customers in.
A worked example
Take a founder who refers four businesses over eighteen months. Two convert quickly, one converts after a long trial, one never pays.
- Referral A pays in month 2 → +3 months
- Referral B pays in month 3 → +3 months
- Referral C pays in month 11 → +3 months
- Referral D never pays → nothing
That founder has banked 9 free months from three conversions. Their renewal has moved from month 12 to month 21. A fourth conversion at any point in the future takes them past a full free year.
Note what did not happen: referral D costs them nothing, embarrasses nobody, and does not expire anyone else’s reward. Unconverted referrals are simply inert.
When this stops being worth thinking about
If you would not recommend KasbPro anyway, none of this arithmetic matters – referrals that do not convert pay nothing, and people are good at telling a genuine recommendation from someone reading a script.
The programme is worth understanding if you are already the person your friends ask what you use for your books. In that case the maths above is just a description of what you were going to do regardless.
Related reading: the full programme terms and what you get on the free plan.
