Retainer Billing

Free
Solo
Team

A retainer is a flat monthly fee you charge a client to reserve a set number of hours. Any hours beyond the included allowance are billed as overage on the same invoice, so your client gets one document and one payment each month.

Retainer billing is available on every plan, including Free, with no limit on the number of active retainers.

Setting up a retainer

Open a client’s detail page and select the Retainer tab.
Click Set up retainer and fill in:
- Monthly flat fee. The fixed amount you charge each month.
- Hours included per month. How many hours the flat fee covers.
- Overage rate per hour. The rate you charge for hours beyond the included allowance.
- Start date. The first day of the retainer. If it falls mid-cycle, your first invoice is prorated.
- Billing day of month. The day your billing cycle turns over, 1 to 31. Pick the day that matches your client’s payment run. Day 31 bills on the last day of shorter months.
- Billing timing. In advance bills the flat fee at the start of each period, with the previous period’s overage on the same invoice. In arrears bills the flat fee and overage together after the period closes. This choice is fixed once the retainer is created; to switch, end the retainer and set up a new one.
- Auto-draft invoices. On by default. When on, Kiaro drafts the invoice on your billing day. When off, you invoice manually and Kiaro reminds you when a period is waiting.
Click Set up retainer.

The Retainer tab then shows a live card with the current billing period, a progress bar of hours used against the period’s allowance, and your estimated invoice total.

A badge next to the period tells you where you stand:

Hours left: for example “12h left”, while you are under 85% of the allowance.
Approaching the cap from 85% up to the full allowance. This is the same point at which your home page flags the retainer.
Hours over: for example “6h over · on next invoice”, once you pass the allowance. The bar grows to show the extra hours in a darker purple, with a marker at the allowance line. Overage is billable time, not an error: it is priced at your overage rate and added to the next retainer invoice.

How billing works

Each billing period runs from one billing day to the next. On the billing day, Kiaro drafts one invoice (when auto-draft is on):

In arrears: the period that just closed, flat fee plus any overage.
In advance: the upcoming period’s flat fee, plus any overage from the period that just closed.

All billable time the retainer counts in a settled period is marked as invoiced when the draft is created. You get a card on your home page when a draft is ready. Review it and click Send when you are happy with it. Nothing is sent automatically.

Invoicing manually

Click Invoice now on the retainer card to draft the next invoice yourself:

If a period is waiting to be billed, the draft is created immediately.
If nothing is due yet, Kiaro asks before billing the upcoming period early. An early invoice carries the flat fee only; overage stays on the clock and rides on the next invoice.

This is handy when a client’s payment team needs the invoice on a specific date, or when you want to bill a mid-month start right away.

If you skip a period, a reminder appears on your home page a few days after the period was due, naming the client and the waiting period. It disappears as soon as the period is invoiced, whether you clicked Invoice now or Kiaro drafted it.

Bill retainer periods from the retainer draft, not with a separate invoice. An invoice you create from the Invoices page is not linked to the retainer, so Kiaro still treats the period as unbilled: the reminder stays, and the period’s hours are counted as overage on the next retainer invoice. If you need to add other charges, such as a fixed fee, add them as lines on the retainer draft before you send it. Deleting a retainer draft puts the period back to unbilled.

Starting mid-month

If a retainer starts mid-cycle, the first invoice covers the partial period at a prorated flat fee, and the included hours are prorated by the same ratio. Proration is based on a fixed 30-day month, so the charge depends only on how many days the partial period covers, never on whether the calendar month has 28, 30, or 31 days. Full months always bill the exact fee you set. The draft is editable, so you can switch it back to the full fee before sending if that is what you agreed with your client.

Changing the billing day

You can change the billing day at any time from Edit. The change applies after the last billed period; if it leaves a gap shorter than a full month, that gap is billed once as a prorated transition invoice, and the new cycle continues from there.

Which time counts

Every billable hour logged on the client’s hourly and mixed projects counts toward the period’s total. There is no per-project allocation, so you do not have to decide which of those projects a given entry belongs to.

Time on the client’s fixed-fee projects does not count. Those projects are billed by their own fee, so their hours never use up the retainer’s allowance or turn into overage.

Because the retainer bills this time, Kiaro never bills it a second time from your time entries while the retainer is active. Those hours are left out of:

Invoices → From Time Entries, which notes how many hours the retainer covers instead of listing them
the home page’s To Bill total and the Uninvoiced card on the Time page
the uninvoiced amounts in Reports and the “Invoice Xh of uninvoiced work” next action
the uninvoiced-value prompt after you log time
the AI command bar and connected AI apps when they list unbilled time or create an invoice from time

They still count toward the retainer’s included hours and overage.

Unused hours expire

Unused hours do not roll over. The allowance resets at the start of each billing period.

Pausing, ending, and editing

Pause. No invoices are generated while a retainer is paused. Time logged during the pause stays uninvoiced and can be billed manually. When you resume, billing picks up from the next billing day; invoice any waiting periods before pausing.
End. The retainer stops generating invoices and moves to your past-retainer history. If overage from the final period is still unbilled, Invoice now drafts one last overage-only invoice.
Edit. Use Edit on the retainer card to change the flat fee, included hours, overage rate, start date, billing day, or auto-draft setting. Changes apply to invoices created after the edit. Moving the start date also moves where billing begins, so no partial period is left before the new start.

A client can have one retainer at a time that isn’t ended, so a paused retainer still counts. Once a retainer is ended, you can set up a new one with updated terms. Included hours can be up to 10,000 a period.

If two changes to a retainer land at the same moment, for example you end it in one tab while it is paused in another, Kiaro applies one and refuses the other, with a message such as “This retainer changed. Refresh and try again.” An ended retainer is never edited, paused or resumed by a change that started before it was ended.

Asking the assistant

The AI command bar can report a client’s retainer status. Ask something like “Show retainer status for Acme” and Kiaro returns the current period, hours used against the allowance, any overage accruing, the estimated invoice total, and when the next invoice is due. It can also list your retainers, including paused or ended ones, and find the clients who are over their hours this period.