Key takeaways
- A client portal gives clients one secure login to upload records, download documents and approve or sign accounts, replacing email attachments.
- BrightManager costs £42.63 per user a month on its Essential plan billed monthly, or £409.25 a year, excluding VAT, with a GDPR-compliant client portal and e-signatures, checked on 6 November 2026.
- IRIS OpenSpace is included for IRIS customers with 1GB of storage free; IRIS's support page prices extra storage at £5 plus VAT a month.
- Karbon lists its Team plan at $59 per user a month billed annually and Business at $89, in US dollars, with a client portal on all plans.
- Senta costs £25.60 a month for the first user billed monthly, with 20% off for annual payment, and clients use it free.
- The ICO recommends encryption for personal data stored and sent over the internet, and says UK GDPR security must be appropriate to the risk.
- Check that a portal's e-signature records who signed, when and what, so you can evidence client approval of accounts and tax returns.
Client portal software gives each client a secure login where they upload records, download documents and approve accounts or returns, so files stop travelling by email. In the UK most portals come bundled with practice management software: BrightManager from £42.63 per user a month, Senta from £25.60, Karbon from $59 in US dollars, and IRIS OpenSpace for IRIS customers. Prices come from each provider’s own page, checked on 6 November 2026, and providers are listed alphabetically, not ranked.
What does a client portal do?
A client portal replaces email for sending and receiving client files. Typical features are:
- secure document upload and download, with an audit trail
- electronic approval or e-signature of accounts, tax returns and engagement letters
- automated reminders for outstanding records
- client requests and checklists
- firm branding on login pages and emails
Many portals come as part of a practice management system, so the portal links to jobs, deadlines and client records. Some firms also add AI tools at the onboarding stage; see AI for client onboarding.
How much does client portal software cost?
Prices range from about £25 to £58 per user a month for UK-priced systems. All figures below were checked on 6 November 2026 and exclude VAT unless noted.
| Provider | Published price | Billing |
|---|---|---|
| BrightManager Essential | £42.63 per user a month | Monthly |
| BrightManager Premium | £57.85 a month | 24-month contract |
| IRIS OpenSpace | 1GB free for IRIS customers | Extra storage £5 a month |
| Karbon Team | $59 per user a month | Annual |
| Karbon Business | $89 per user a month | Annual |
| Senta | £25.60 first user a month | Monthly |
TaxDome, another portal used by UK firms, blocked our check of its pricing page, so it is not included here. Check its prices directly.
BrightManager
BrightManager, formerly AccountancyManager, is practice management software for UK and Irish firms with a GDPR-compliant client portal supporting e-signatures and forms. Essential is £42.63 per user a month billed monthly, or £409.25 a year, for 2 to 12 users, with a 30-day free trial.
Premium (24-month contract, with one free extra user) and Advanced (12-month contract) are each £57.85 a month or £694.26 a year for a single user, and add a branded portal and proposal tool. Onboarding tools include engagement letters, AML checks and HMRC agent authorisation requests.
IRIS OpenSpace
IRIS OpenSpace is the portal in IRIS Accountancy Suite. Clients exchange documents and approve or sign them from a browser, with automatic reminders after 7, 14 or 30 days and an e-checklist of documents awaiting approval. You can white-label the portal and embed it on your website.
IRIS customers get 1GB of storage free. IRIS’s support page prices extra storage at £5 plus VAT a month, though the article dates from 2014. Non-IRIS firms must contact IRIS for a price; the sales line is 0344 815 5550.
Karbon
Karbon is a workflow and practice management platform with a client portal on every plan, for task and document sharing. Team is $59 per user a month billed annually ($79 monthly) and Business is $89 ($99 monthly); Enterprise is quoted. Monthly billing is only for teams of 4 or more.
The page offers a GBP currency selector but showed only US dollar prices when we checked. E-signatures use credits bought in bundles, from 100 credits for $100.
Senta
Senta is practice management software, now shown as Senta by IRIS. It costs £25.60 a month for the first user, billed monthly in arrears, with 20% off for annual payment in advance and further discounts for extra users. Clients use it free.
The pricing page does not set out portal features in detail, so ask for a demo of the client side before buying.
Is a client portal more secure than email?
Usually, if it is set up well. The ICO’s guide to data security says UK GDPR requires security appropriate to the risk, and recommends encryption for personal data stored and sent over the internet. Client records include bank statements, payslips and ID documents, so the risk is high.
Ask each provider:
- where data is hosted and whether it is encrypted at rest and in transit
- whether two-factor login is available for staff and clients
- what the audit trail records for uploads, downloads and signatures
- how you export your data if you leave
Moving document requests into a portal can also reduce the risk of clients acting on fake emails asking them to send documents; see AI invoice fraud.
Which applies to you?
- If you already use IRIS software, start with IRIS OpenSpace, which is included with 1GB free.
- If you want portal, workflow and onboarding in one UK-priced system, compare BrightManager and Senta.
- If you run a larger team on a workflow-first platform, price Karbon, remembering its prices are in US dollars.
- If you need branded e-signing for engagement letters, check which plan includes branding and how signatures are charged.
What to do now
- List what clients send you and what you send them.
- Decide whether you want a standalone portal or one inside practice management.
- Book demos and test the client side on a phone.
- Check contract length, VAT and price per extra user.
- Plan client onboarding, including AML checks.
Frequently asked questions
What is the cheapest client portal for UK accountants?
Of the UK-priced systems checked on 6 November 2026, Senta has the lowest published price at £25.60 a month for the first user. IRIS OpenSpace comes with 1GB free for existing IRIS customers.
Does BrightManager have a client portal?
Yes. BrightManager includes a GDPR-compliant client portal with e-signatures and forms, and its Premium and Advanced plans add a branded version.
Is Karbon priced in pounds?
Karbon’s pricing page shows US dollar prices: $59 per user a month for Team and $89 for Business, billed annually. A GBP selector is offered, so confirm a sterling quote.
Can clients sign accounts through a portal?
Yes. IRIS OpenSpace, BrightManager and Karbon all support electronic approval or e-signatures. Check what the audit trail records before relying on it.
Is using a portal required under GDPR?
No. UK GDPR requires security appropriate to the risk, not a specific tool, but the ICO recommends encrypting personal data sent over the internet.
Sources
Rates, thresholds and rules in this guide were checked against HMRC and GOV.UK guidance on 6 November 2026. Tax rules change, so check the current position on GOV.UK or with a qualified adviser before acting. This guide is general information, not personal advice.