Skip to content

How Bandwidth Is Billed#

Deep Thought spent seven and a half million years computing the answer to life, the universe and everything, and then said "42". We measure your bandwidth every five minutes and, at the end of the month, tell you something slightly more useful than 42: whether you stayed inside your commitment or went over it. This page explains how that sum is done and how it shows up on your invoice.

Two kinds of commitment#

The bandwidth item in your contract uses one of two measures. Which one applies, the included amount and the overage unit price are written in your contract or its amendment, and that is the only basis.

TB quota Mbps commitment (95th percentile)
What is measured Total data transferred during the period (in + out) Traffic rate for every 5 minutes of the period
Compared with The included TB quota The committed rate (commit)
Overage The part above the quota, rounded up to a whole TB The part of the 95th percentile above the commit, rounded up to a whole Mbps

What is the 95th percentile? All 5-minute measurements of the period are sorted from lowest to highest and the top 5% is dropped; the highest of the rest is the 95th percentile. Inbound and outbound traffic are calculated separately and the larger one counts. In practice this means short bursts do not affect your invoice. In a 30-day month, peaks adding up to less than 36 hours fall inside the 5% that is dropped.

The measurement period#

  • A measurement period is one month and follows your contract's renewal day: if your contract renews on the 3rd, the period runs from the 3rd to the 3rd of the next month.
  • Period boundaries are midnight, Türkiye time.
  • A contract billed yearly or quarterly is still measured monthly.
  • On the invoice the period is written with its last day: the 03.10 - 03.11 period reads "03.10.2026 - 02.11.2026".
  • Partial period: if your service started in the middle of a period, or your contract ended in the middle of one, the TB quota is scaled down in proportion to the shorter window; the Mbps commitment stays the same, because a rate does not shrink with time.

How an overage reaches your invoice#

The overage is calculated after the period closes.

  • On a contract billed monthly, the overage goes onto your next monthly invoice as a separate line. If the measurement is ready on the morning the period closes it goes onto that day's invoice, otherwise onto the next one; the line is never lost: it goes onto the first renewal invoice after the overage is priced, and it says which period it belongs to.
  • On a contract without a monthly invoice (yearly or quarterly), the overage is billed on its own invoice when the period closes; it does not wait for your yearly invoice.

An invoice that carries an overage is issued once our team has checked and approved the measurement: you are notified that day, and the payment term starts that day too.

The line explains where the figure comes from: the service name, the measurement period, the overage, the measured usage, the included amount and the unit price. For example, on a TB quota:

36 TB Bant Genişliği - Ankara: 03.10.2026 - 02.11.2026 döneminde 3 TB aşım (ölçülen 38,41 TB, dahil 36 TB, unit price/TB)

That reads: a 3 TB overage in the 03.10.2026 - 02.11.2026 period, 38.41 TB measured, 36 TB included. On an Mbps commitment the period's 95th percentile and the commit take the place of the measured usage. Invoice lines are written in Turkish, like the rest of the e-invoice.

Currency. If the overage unit price is in a currency other than your contract's, it is converted at the last TCMB (Central Bank of the Republic of Türkiye) forex selling rate published before the day the measurement period ends. The rate used and its date are written on the line, so you can check the sum yourself. VAT and any exemption apply exactly as they do to the other items of your contract.

Which terms are used? An overage is calculated with the method (TB quota or 95th percentile) and the overage unit price written in your contract or its amendment. A price change in our catalogue does not change your terms; they change only with an amendment. No overage is billed retroactively.

Don't Panic

An overage is a measurement, not an estimate: nothing is billed before the period closes, and the sum uses only the period's final, complete measurement. If a figure looks odd, open a support request and we will go through the measurement with you, period by period.

Mbps: the notice before the period ends#

On an Mbps commitment, the moment an overage becomes certain can be worked out before the period ends. Once the number of 5-minute measurements above the commit exceeds the 5% that is dropped, the 95th percentile cannot fall below the commit even if your traffic dropped to zero for the rest of the period. When that happens we may send one notice per period to the members of your team who can see your contracts (your billing contact and your technical team).

  • The notice gives the 95th percentile measured so far, the commit and the end date of the period; it does not give an amount, because the exact amount is set when the period closes.
  • The notice is for your information: the exact overage is calculated at the end of the period and reaches your invoice as described above.
  • There is no in-month notice for a TB quota.

No notice does not mean no overage

The notice is a courtesy, not a precondition of the invoice. The exact sum is always done at the end of the period. Rarely, if a measurement period is shortened backwards (for example because your contract's renewal date changes), a period that got a notice can close without an overage; then nothing is billed. Marvin would find something gloomy to say about that too, but we are not asking him.

If the measurement fails#

For a period's overage to be calculated, at least 95% of the 5-minute measurements expected in that period must have arrived.

  • If fewer arrived, the period closes as "not measured" and no overage is billed for that period. We do not fill missing measurements with guesses; we do not charge you for something we do not know.
  • If our measurement system is briefly unreachable, your invoice does not wait for it; the overage line goes onto the next invoice once the measurement is done.

When your contract ends#

  • The final period that is running is measured up to the moment the contract ends; the TB quota is scaled to that shorter window, the Mbps commitment does not change.
  • Overage lines not yet invoiced go onto one final invoice when the contract ends.
  • If the final period has an overage, it is billed on its own final invoice when the period closes. An overage is service you have already used; it does not disappear because the contract ended, and traffic after the end is not counted either.