Invoice Koi vs Billdu
Two subscriptions. Compare what each one buys.
Billdu starts at $7.99 a month for Lite, with no free plan. Invoice Koi is about US$8.33 a month, billed yearly, with every feature on one plan.
Last checked 7 September 2026. US list prices.
On Google Play now. Coming soon to iPhone. Have the app? Open it
Billdu or Invoice Koi?
Ten clients is a good first month, not a business.
Choose Billdu if
- You want a barcode scanner, which Invoice Koi does not have.
- You want it in a browser as well as the phone.
- You want to know when a client opened the invoice.
Choose Invoice Koi if
- You have more than ten clients, or intend to.
- You want receipts and time tracking without them being a higher tier.
- You want one set of features rather than a ladder of plans.
What Billdu is good at
Billdu is broad. Web and phone, expenses, e-signature, a barcode scanner, and an online store, which is more surface area than anything else at this price.
The catch
Lite is ten clients. Not ten a month, ten. A tradesperson passes that in two weeks, and the plan that lifts it is not the one on the front of the page.
The ten rows that decide it
| Feature | Invoice Koi | Billdu |
|---|---|---|
| Best for | One person invoicing from a phone, between jobs | Sellers who want web, phone and a barcode scanner |
| What it costs | Subscription, with a free trial where your store offers one | $7.99 a month for Lite |
| Invoices | No cap | Cap not stated |
| Estimates or quotes | No cap | On a higher plan |
| Clients | No cap | 10 clients |
| Invoices free of vendor branding | Included | Included |
| Accept card payments | Included | Not stated |
| Receipt scanning | Included | Not stated |
| Jobs and job organization | Included | Not stated |
| Users on the account | 1 user, crew plans add seats | 1 user |
| Web access | Not offered | Included |
| Sync and backup across devices | Included | Included |
All 59 features, and the tier each one sits in
A paid tier includes its own free tier, so a mark means available at that price or below. Of the 59, 5 are better here, 4 better in Billdu, 9 tied, and 41 neither, or not stated.
| Feature | Invoice Koisubscription | Billdu$7.99 a month for Lite | Who has it |
|---|---|---|---|
| Documents | |||
| Invoices | ○ | ○ | Tied |
| Estimates or quotes | ○ | ▲ | Invoice Koi |
| Clients | ○ | 10 clients | Tied |
| Turn an estimate into an invoice | ○ | · | Not stated |
| Recurring invoices | ○ | ▲ | Invoice Koi |
| 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 | ○ | · | Not stated |
| How the document looks | |||
| Your logo on the document | ○ | · | Not stated |
| Your brand or accent color | ○ | · | Not stated |
| Choice of templates | ○ | · | Not stated |
| Invoices free of vendor branding | ○ | ○ | Tied |
| Rename the field labels | ○ | · | Not stated |
| Photos and attachments | ○ | ○ | Tied |
| Terms and conditions block | ○ | · | Not stated |
| License and insurance details | – | · | Not stated |
| Your own signature | ○ | · | Not stated |
| Client e-signature | ○ | ○ | Tied |
| Getting paid | |||
| Accept card payments | ○ | · | Not stated |
| Bank transfer or ACH | – | · | Not stated |
| Tap to Pay in person | – | · | Not stated |
| Deposits or milestone payments | ○ | · | Not stated |
| 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 | ○ | ○ | Tied |
| Receipt scanning | ○ | · | Not stated |
| Time tracking | ○ | · | Not stated |
| Jobs and job organization | ○ | · | Not stated |
| Schedule visits or a calendar | ○ | · | Not stated |
| Routing or GPS | – | · | Not stated |
| Reports | ○ | · | Not stated |
| Export CSV, spreadsheet or PDF | ○ | · | Not stated |
| Accounting sync | – | ▲ | Them |
| Bank feed import | – | · | Not stated |
| Barcode scanner | – | ▲ | Them |
| Leads or a CRM | – | · | Not stated |
| Track client activity | ○ | · | Not stated |
| Request client reviews | – | · | Not stated |
| A marketing site for you | – | · | Not stated |
| An AI assistant | ○ | · | Not stated |
| Voice note into an invoice | ○ | · | Not stated |
| Read a document and answer on it | ○ | – | Invoice Koi |
| Account and scale | |||
| Mobile app | ○ | ○ | Tied |
| Web access | – | ○ | Them |
| Sync and backup across devices | ○ | ○ | Tied |
| Users on the account | 1 user, crew plans add seats | 1 user | Tied |
| More than one business | ○ | · | Not stated |
| Priority support | one to two days | ▲ | Invoice Koi |
- ● In the free tier
- ○ In the cheapest paid plan
- ▲ Only on a higher plan
- – Not offered
- · Not stated on their page
- 3 a month Included, but capped or charged at this rate
What is free, and what the subscription buys
Setting up your business and writing drafts is free. Issuing an invoice, estimate or receipt needs a subscription. Eligible new iOS subscribers: two weeks free on annual, one week on weekly. Nothing starts until you confirm the purchase. Without a trial, the displayed price applies immediately.
- Install the app and set up your business
- Add your clients and your price book
- Write drafts of invoices and estimates
- Send unlimited invoices, estimates and receipts
- Cloud storage for every photograph, on any phone
- Unlimited AI scanning of receipts and documents
- AI voice notes into invoices, no daily limit
- Priority support, in one to two working days
US App Store solo prices. Prices and offers vary by country and store. Your local price appears in the app before purchase. Renews automatically until cancelled in your store account settings. Your records stay yours. After expiry, view, export or resend issued records and record or collect outstanding payments. New documents need a subscription or eligible trial, except where existing access is preserved. Existing customers keep their promised core document access.
Switching from Billdu
If Billdu can export your clients or items as a spreadsheet (CSV), Invoice Koi reads the file, matches the columns by their headings and only ever adds: nothing already on your phone is removed. You can do it before you subscribe.
Common questions
Is Invoice Koi cheaper than Billdu?
Both charge to send. As checked on 7 September 2026, Billdu's cheapest way in is $7.99 a month for Lite. Invoice Koi is free to set up and draft in, and sending is an annual solo plan at US$99.99 billed yearly (about US$8.33 a month), or a weekly solo plan at US$9.99 billed weekly (US App Store prices). The app shows your local price from the store, with any free trial you are eligible for, before you buy.
What does Invoice Koi include that Billdu puts on a higher plan?
Four of the 59 features compared are in Invoice Koi's subscription and only on a higher Billdu plan, including “Estimates or quotes”, “Recurring invoices” and “Automatic payment reminders”.
What does Billdu do that Invoice Koi does not?
Four things, including “Know the invoice was opened”, “Accounting sync” and “Barcode scanner”. If one of those is what you need, Billdu is the better pick.
Does Invoice Koi take card payments?
Yes. After Stripe setup, Koi can collect card payments online through a payment link. Koi charges 0.35% with a subscription, or 0.7% + $0.10 without one, plus Stripe processing fees. Payments recorded manually have no Koi fee.
Draft first, subscribe to send
Draft free. Subscribe to send unlimited invoices with your own logo and no watermark.
On Google Play now. Coming soon to iPhone. Have the app? Open it
iPhone and iPad, iOS 16.4 or later.
Where these numbers come from
Every Billdu cell was read from their own pricing page on 7 September 2026, at US list prices in US dollars. Billdu is read from its published plan comparison. Unlisted features and rates are marked as not stated. Platform fees are separate from processor fees. Report a correction.
Product names and logos belong to their owners. This comparison is not endorsed by or affiliated with Billdu.