Early access · Sage 50 Accounts UK & Ireland
The Sage 50 API that Sage never shipped
Sage 50 has no web API. Daybook gives you one: REST endpoints for customers, suppliers, invoices, payments and the nominal ledger. We look after the Windows connector, Sage updates and remote setups.
For SaaS teams whose customers keep asking “do you work with Sage 50?”
{
"supplier_ref": "ACME001",
"date": "2026-10-12",
"reference": "INV-4471",
"lines": [{
"nominal_code": "5000",
"net": 120.00,
"tax_code": "T1",
"details": "Packaging"
}]
}| Type | Date | A/C | N/C | Ref | Details | Net | T/C | Tax |
|---|---|---|---|---|---|---|---|---|
| PI | 12/10/2026 | ACME001 | 5000 | INV-4471 | Packaging | 120.00 | T1 | 24.00 |
Your customers use Sage 50. Your product can't reach it.
Sage 50 runs on a Windows PC or server, not in the cloud. There's no web API to call, so connecting to it today means picking one of three compromises.
How it works
Your customer installs one small connector. You get an API. Everything in between is our job.
- Your app
- HTTPS · your API key
- Daybook API
- outbound-only connection
- Daybook connectoron the Sage 50 PC or server
- Sage's own data interface
- Sage 50 Accounts
-
Your customer connects Sage 50 once
They install the Daybook connector on the machine that runs Sage 50. It only makes outgoing connections, so their IT team doesn't need to open firewall ports. Remote desktops and hosted Sage setups work too.
-
You call a REST API
One API key, JSON in and out, predictable endpoints, and webhooks when something changes in Sage 50.
-
We handle the awkward parts
Sage version updates, queuing requests to a desktop app, retries when the PC is switched off, and clear errors when something on the customer's side needs fixing.
An API that looks like every other API you use
No SDK to install, no XML, no Windows on your side.
- Writes return Sage's own transaction numberso you can reconcile against the audit trail.
- Requests queue when the PC is offand you get a clear status instead of a timeout.
- Webhooks for changeswhen customers, invoices or payments change in Sage 50.
- A free sandboxwith a test Sage 50 company, so you can build before your first customer connects.
Request
# List suppliers in a customer's Sage 50 company
curl https://api.daybookapi.com/v1/companies/cmp_8f2k/suppliers \
-H "Authorization: Bearer sk_test_..."Response
{
"data": [
{
"id": "sup_ACME001",
"account_ref": "ACME001",
"name": "Acme Packaging Ltd",
"balance": 1840.50,
"default_nominal_code": "5000",
"default_tax_code": "T1"
}
],
"next_cursor": null
}What you can read and write
The core of Sage 50 Accounts, as plain resources. Need something that isn't listed? Tell us when you sign up. Early-access teams shape the roadmap.
| Resource | Endpoint | Access |
|---|---|---|
| Customers | /customers | Read, write |
| Suppliers | /suppliers | Read, write |
| Nominal codes | /nominal-codes | Read, write |
| Sales invoices and credit notes | /sales-invoices | Read, write |
| Purchase invoices and credit notes | /purchase-invoices | Read, write |
| Receipts and payments | /payments | Read, write |
| Bank accounts and transactions | /bank-accounts | Read, write |
| Products and stock levels | /products | Read, write |
| Departments and projects | /departments, /projects | Read, write |
| Tax codes | /tax-codes | Read |
| Audit trail | /transactions | Read |
Spend and expenses
Sync card spend, receipts and reimbursements as they happen.
AP and approvals
Pull suppliers and nominal codes, post approved bills.
Credit control
Read sales ledgers and post receipts.
Field service
Turn completed jobs into sales invoices.
Ecommerce and stock
Keep orders, stock levels and invoices in step.
Lending
Read financials with your customer's consent.
How it compares
The same job, done four ways.
| Build your own | CSV export | Consultant or middleware | Daybook | |
|---|---|---|---|---|
| Live sync | Yes | No | Usually | Yes |
| Work for your team | Months, then forever | Low | Low | Days |
| Work for your customer | Install your connector | Manual import, every time | A consultant project | One install |
| Sage version updates | You | n/a | Them | Us |
| Remote and hosted setups | You | n/a | Varies | Supported |
| Who pays | Your developers, plus Sage's developer programme | You, in lost deals | Your customer: setup fee and monthly | You, per connected company |
Pricing
You pay for the Sage 50 companies your customers connect. Nothing else.
£39 per connected Sage 50 company, per month
- Free sandbox with a test Sage 50 company
- No setup fees
- Volume pricing from 50 connected companies
Founding partners
The first 10 teams get 50% off for 12 months. In return, you join a 30-minute call each month and tell us what's missing.
Apply as a founding partnerQuestions
Is this made by Sage?
No. Daybook is an independent product. It isn't affiliated with, endorsed by or sponsored by The Sage Group plc.
Which versions of Sage 50 are supported?
Sage 50 Accounts for the UK and Ireland, current versions. We'll publish the exact version list before launch. Sage 50 in the US and Canada are different products and aren't supported yet.
What does my customer need to install?
A small Windows connector on the machine that runs Sage 50. It runs in the background and only makes outgoing connections, so no firewall changes are needed.
What if Sage 50 runs on a remote desktop or with a hosting provider?
That's a setup we're designing for. The connector goes on the server where Sage 50 runs, not on each user's PC.
Do you keep a copy of my customers' accounting data?
No. Data passes through Daybook encrypted in transit. Logs record request details such as time, endpoint and status, not accounting content.
What happens when my customer's PC is switched off?
Requests wait in a queue and run when the connector comes back online. You get a clear status rather than a timeout.
When can I start?
We're onboarding the first teams now. Request early access and we'll reply within two working days.
Get early access
Tell us a little about your product and how your customers use Sage 50. We'll reply within two working days to set up a sandbox and a short call.
Request received
We'll reply to within two working days to set up a sandbox and a short call.