Almost every UK accountancy firm has had the same conversation internally in the last two years. The portal isn’t working. Clients don’t log in. Documents come back late, in the wrong format, or not at all. Partners spend evenings on chase calls for information that should have arrived by itself. And yet the portal was the answer to exactly this problem — so what went wrong?
The short version: the portal was designed for the firm, not for the client. The client sees it once or twice a year, can’t remember the password, opens it on their phone, gives up, and falls back to email or — increasingly — WhatsApp. The data on this is unambiguous when firms look at it honestly.
The numbers firms actually see
We’ve spoken to dozens of UK firms about their portal response rates, and the pattern is consistent. Portals send an email asking the client to log in and complete an intake. The measurable outcomes break down roughly like this:
- 30–40% of clients respond within a week of the first request.
- Another 20–30% respond after one or two chase emails or a phone call from the firm.
- The remaining 30–40% require multiple chases, partner calls, or in-person prompting — often right up to the filing deadline.
By contrast, firms that have switched the first-touch channel to WhatsApp — usually via the WhatsApp Business API — see something quite different:
- 70–80% of clients reply within 24 hours of the first message.
- 85–90% reply within a week with one gentle nudge.
- The 10–15% who don’t respond on WhatsApp tend to be the same clients who didn’t respond on the portal either — and they need a phone call regardless.
These ranges aren’t industry-standardised data; they’re what UK firms report when they measure it. But the gap is wide enough that the directional story is firm: WhatsApp roughly doubles first-touch response rates compared with portal-and-email intake.
Why portals underperform
Portals fail for structural reasons, not because the software is bad. The problems are about how an individual taxpayer relates to a tool they touch once a year.
Clients don’t install apps for things they do once a year
A landlord with two flats, or a sole trader filing a single Self Assessment, isn’t going to download a dedicated app, create an account, verify an email, and set a password for something they’ll use twice. They’ll start the process, encounter friction, and bail. The behavioural economics of this are settled — every step of friction in a one-off task halves completion. Portals stack four or five steps before the client can even start.
Passwords get lost — every year
The portal password the client set last January is gone. They reset it. The reset email goes to spam. They eventually log in and discover the interface has changed. By the time they reach the screen where they’re supposed to upload anything, they’ve spent ten minutes and are mildly annoyed. They close the tab and go back to email the partner directly. The partner’s admin then re-uploads everything into the portal on the client’s behalf, defeating the point.
Mobile portals are mostly bad
Most UK firm portals are built mobile-responsive but not mobile-first. The upload flow on a phone — taking a photo of a completion statement, finding it in the camera roll, attaching it through a small form — is materially worse than the equivalent flow in a chat app. Clients who do log in on mobile frequently can’t complete the upload and put the task off until they’re “at a computer”. That moment often doesn’t come.
The notification problem
Portal emails sit in inboxes alongside several hundred other messages a week. They get archived, missed, or filtered. There is no second-line notification. A WhatsApp message, by contrast, triggers a push notification on a device the client uses several times a day. The probability of being seen is an order of magnitude higher.
Why WhatsApp wins for intake
The wins are mirror images of the portal failures.
It’s already installed
Penetration of WhatsApp among UK adults is roughly 80% and higher again among the working-age population most firms deal with. There is no install, no account creation, no password. The client opens an app they already use every day.
Photos and documents send in two taps
The mobile upload flow on WhatsApp is the best in the world, because it’s been refined by billions of users. Tap the paperclip, tap the photo, send. Or take a photo directly from the chat. The cognitive load is near zero.
Push notifications work
A WhatsApp message gets a notification the client actually sees. A gentle follow-up two days later — “just checking, did you get a chance to send the council tax bill?” — feels like a natural conversation rather than a chase.
Worked example: what this does to firm economics
The headline response-rate numbers sound abstract. The firm-level economics are concrete. Consider a mid-sized firm with 400 personal tax clients. Intake for Self Assessment plus, from this year, MTD ITSA quarterly cycles. A partner’s blended cost to the firm is roughly £150 per hour fully loaded.
Under the portal model:
- ~140 clients (35%) respond cleanly and need no chasing.
- ~120 clients (30%) need one or two chase emails plus a follow-up call — say 15 minutes of admin and partner time per client. That’s 30 hours across the cohort.
- ~140 clients (35%) need multiple chases, partner calls, and occasionally a face-to-face meeting just to get documents in. Average 45 minutes per client. 105 hours.
Total chase time: ~135 hours, of which maybe a third is partner time (~45 hours at £150/hr = £6,750) and the rest is admin and senior staff time. Across a year, the chase load alone consumes the equivalent of 3.5 partner weeks.
Now run the same firm on a WhatsApp-first intake model with a 75% clean response rate:
- ~300 clients (75%) respond cleanly. No chase needed.
- ~60 clients (15%) need a single follow-up message — 5 minutes each. 5 hours.
- ~40 clients (10%) need a phone call or in-person prompt — 30 minutes each. 20 hours.
Total chase time: ~25 hours. A reduction of 110 hours per year for one firm with 400 clients — about 2.5 partner weeks reclaimed. The same logic compounds across the new MTD ITSA quarterly cycle, where intake happens four times a year rather than once. On the quarterly cycle, the saving is closer to 10 partner weeks annually for the same firm.
That’s the firm-level case for changing channel. It isn’t about clients liking WhatsApp more (although they do). It’s about partner time stopping leaking into admin that shouldn’t need a partner at all.
“But what about clients who don’t use WhatsApp?”
There’s always a 15–20% of any firm’s client base who don’t use WhatsApp — usually older clients, or clients with deliberate digital-minimalism preferences. They are not a reason not to move; they are a reason to keep email as a fallback channel. The point of moving the default to WhatsApp is the 80%, not the 20%. The 20% get the same email intake they always had, and frequently the same chase pattern they always had.
The economics still work overwhelmingly in favour of switching, because the 80% who respond cleanly free up the time you need to properly serve the 20% who don’t.
“But what about compliance and audit trail?”
This is the question every firm partner asks second. The answer is that the consumer WhatsApp app is not what you use — the WhatsApp Business API is. The Business API, accessed via an official Business Solution Provider, gives you:
- Full message history retained in your firm’s systems, timestamped and exportable.
- Audit-grade logs of who sent what, when, and to whom.
- Document storage in your own systems, not on a client’s phone, with metadata linking each artefact to the client and the work it relates to.
- Authentication signals — verified business profile, message templates approved in advance — so clients know the message is from your firm and not a scam.
- GDPR-compliant data handling, with appropriate processor agreements with Meta.
For a firm that’s been on email for a decade, the audit trail is better, not worse. Email retention is patchy, mailbox rules are uncontrolled, and attachments routinely live on local drives. A Business-API-driven intake channel is one of the tighter audit-trail options available to a firm.
What this looks like as a default
The mature pattern is straightforward:
- Default to WhatsApp for client intake messages and document collection.
- Email fallback for clients who don’t use WhatsApp, sent automatically when WhatsApp delivery fails.
- Portal for output, not input — final returns, engagement letters, e-signatures. The portal is good at outbound; it’s bad at inbound.
- Phone call as the third line for the small minority who don’t respond to either channel.
The firms that are quietly winning on response rate aren’t using a single channel. They’re using the right channel for the right step. WhatsApp is the right channel for the bit partners hate most: chasing.
If chase load is your problem, talk to us
Otto is the intake and prep engine for UK accountancy firms. WhatsApp-first by default, email fallback for the clients who prefer it, and a full audit trail your compliance team can sign off on. If response rates are the bottleneck in your practice, we’d like to hear about it.
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