You should not have to pay to find out.
Invoice Simple starts at $6.99 Essentials, with no free plan behind it. Invoice Koi is free for a hundred invoices a year, with 33 of the 59 features compared here in the free app, and one paid plan at $99.99 a year.
Last checked 7 September 2026. US list prices.
A paid plan that still counts your invoices is a trial with a direct debit attached.
Invoice Simple earns its name. It is quick to understand, the documents look tidy, and it is one of the few here that tells you when a client has opened the invoice.
The catch
The counting does not stop when you start paying. Essentials is the cheapest way in and it still meters what you send, so the thing you bought the plan to do is the thing it keeps score of.
A paid plan that still counts your invoices is a trial with a direct debit attached.
Two questions, and they have different answers: what you get for nothing, and what the least you can pay actually buys. Pick one.
A paid tier includes its own free tier, so a mark means available at that price or below. 22 rows go our way, 3 theirs, 1 are the same in both, and 33 are neither or unstated.
| Feature | Invoice Koifree, then $99.99 a year | Invoice Simple$6.99 Essentials | Cheaper for a tradesperson |
|---|---|---|---|
| Documents | |||
| Invoices | 100 a year | 3 a month | Invoice Koi |
| Estimates or quotes | ● | ○ | Invoice Koi |
| Clients | ● | · | Not stated |
| Turn an estimate into an invoice | ● | ○ | Invoice Koi |
| Recurring invoices | ● | · | Not stated |
| Credit notes | ● | · | Not stated |
| Work orders | – | · | Not stated |
| Change orders | – | · | Not stated |
| Client contracts | – | · | Not stated |
| Document or project templates | ● | · | Not stated |
| Price book of saved items | ● | ○ | Invoice Koi |
| How the document looks | |||
| Your logo on the document | ● | · | Not stated |
| Your brand or accent colour | ● | · | Not stated |
| Choice of templates | ● | ▲ | Invoice Koi |
| No vendor branding on it | ● | ● | Level |
| Rename the field labels | ● | · | Not stated |
| Photos and attachments | ● | ▲ | Invoice Koi |
| Terms and conditions block | ● | · | Not stated |
| Licence and insurance details | – | · | Not stated |
| Your own signature | ● | ▲ | Invoice Koi |
| Client e-signature | ○ | ▲ | Invoice Koi |
| Getting paid | |||
| Accept card payments | – | ○ | Them |
| Bank transfer or ACH | – | · | Not stated |
| Tap to Pay in person | – | · | Not stated |
| Deposits or milestone payments | ○ | ▲ | Invoice Koi |
| Record partial payments | ● | · | Not stated |
| Pass processing fees to the client | – | · | Not stated |
| Tips | – | · | Not stated |
| Automatic payment reminders | ● | ▲ | Invoice Koi |
| Overdue alerts to you | ● | · | Not stated |
| Know the invoice was opened | – | ○ | Them |
| A link the client opens | – | · | Not stated |
| Client statements | ○ | · | Not stated |
| Homeowner financing | – | · | Not stated |
| Lending or capital for you | – | · | Not stated |
| Running the business | |||
| Expense tracking | ● | – | Invoice Koi |
| Receipt scanning | 5 a day | – | Invoice Koi |
| Time tracking | ● | – | Invoice Koi |
| Jobs and job organisation | ● | – | Invoice Koi |
| Schedule visits or a calendar | ● | – | Invoice Koi |
| Routing or GPS | – | – | Neither |
| Reports | ● | ▲ | Invoice Koi |
| Export CSV, spreadsheet or PDF | ● | · | Not stated |
| Accounting sync | – | – | Neither |
| Bank feed import | – | – | Neither |
| Barcode scanner | – | · | Not stated |
| Leads or a CRM | – | – | Neither |
| Track client activity | ○ | · | Not stated |
| Request client reviews | – | · | Not stated |
| A marketing site for you | – | – | Neither |
| An AI assistant | 5 a day | – | Invoice Koi |
| Voice note into an invoice | 5 a day | – | Invoice Koi |
| Read a document and answer on it | 5 a day | – | Invoice Koi |
| Account and scale | |||
| Mobile app | ● | ○ | Invoice Koi |
| Web access | – | ○ | Them |
| Sync and backup across devices | books; pictures on Pro | ○ | Invoice Koi |
| Users on the account | 1 user | ○ | Invoice Koi |
| More than one business | ● | · | Not stated |
| Priority support | one to two days | · | Not stated |
The same on all eleven of these pages. One price, billed once a year, with no seat maths and no plan above it. Free is one person and their own books, counted at 100 invoices a year and at nothing else. Pro is what leaves the phone: the photographs on a server, the reading, and the paperwork a client signs or opens.
Everything in Free is in Pro too. Pro is sold through the App Store, so the price you are shown is your own country's.
No trial clock, no card, and no invoice with somebody else's name at the bottom of it. If Pro is worth $99.99 a year to you, it will still be there in a month.
iPhone and iPad, iOS 16.4 or later.
Every Invoice Simple cell was read from their own pricing page on 7 September 2026, at US list prices in US dollars. Invoice Simple is read from its published plan comparison. A blank means they do not name the feature on the page where they ask for money, and we count that as not included rather than guessing in our own favour. Processing rates appear only where the vendor is itself the processor: read a missing rate as unstated, never as free. If we have a line wrong, tell us and we will change it.
Invoice Simple and every other name and logo on this page belong to their owners. They are here to say which product is being compared, which is the only reason a comparison may use them, and nothing here is endorsed by or affiliated with them.