Customizing Booking Email Templates

Shillinq sends three kinds of branded transactional emails for every booking lifecycle event:

• Booking Confirmation — sent immediately after a booking is confirmed.
• Booking Reminder — sent a configurable number of hours before the booking starts.
• Booking Cancellation — sent when a booking is cancelled.

Templates are declarative: subject, HTML body, plain-text body, branding and lifecycle live on the template record. Dispatch and retries are handled by OpenRegister's notification engine — there is no separate email service to operate.

Outcomes

• One published template per type, per locale, branded for your organization.
• Operator-only customization of branding (logo, accent colour, footer) and text — no developer involvement required.
• Versioned rollout: a published template stays active until the new draft is published.

Prerequisites

• The template-administrator (or booking-administrator) role.
• A CDN or document-store URL hosting the organization logo image.

1. Open the template list

In the Shillinq navigation choose Communication →:

• Confirmation Templates
• Reminder Templates
• Cancellation Templates

Each list shows every template with its locale (nl/en), subject line, status (draft, published, archived) and first-activated timestamp. Six default templates ship with the app — two per type, one Dutch (nl) and one English (en) — already published. Use them as a starting point or clone them to a draft for editing.

2. Create a draft

Click Create and fill in:

Field	Notes
Name	Internal label shown in the admin list.
Locale	nl or en. The notification engine picks the locale matching the customer's language preference at dispatch.
Subject line	≤78 characters after variable substitution. Test with a long booking reference to be safe.
HTML body	Inline styles only. Allowed elements: div, p, h1-h6, a, img, table, tr, td, th, tbody, thead, ul, ol, li, br, span, strong, em, b, i, hr. No <style>, <link>, <script> or JavaScript.
Plain-text body	Always required as the fallback for email clients without HTML rendering.
Logo URL	CDN or document-store URI. Inline base64 images are rejected — they bloat email size and cannot be refreshed without resending.
Accent colour	Six-digit hex code (e.g. #0066cc).
Footer text	Address, contact, legal notices. Free text.
Sender name / address	Optional. Overrides the global default at dispatch.

For reminder templates also set Hours before booking (1–720). For cancellation templates the Include cancellation reason toggle exposes {{cancellationReason}} as a variable in the template body.

The template saves as draft — it is not yet dispatched.

3. Variable reference

Templates use {{variableName}} placeholders. The notification engine substitutes them at dispatch.

Standard variables (all templates)

Variable	Example	Description
{{customerName}}	Femke Jansen	Full name of the customer.
{{bookingRef}}	BK20260521042	Booking reference / ID.
{{bookingDate}}	22 mei 2026	Booking date in the customer locale.
{{bookingTime}}	10:00	Booking start time in the customer locale.
{{bookingLocation}}	Kantoor Amsterdam, Kamer 3	Physical or virtual location.
{{organizationName}}	Example BV	Organization or business name.

Reminder-only variables

Variable	Example	Description
{{hoursUntilBooking}}	24	Hours until booking start (calculated at dispatch).

Cancellation-only variables (when "Include cancellation reason" is on)

Variable	Example	Description
{{cancellationReason}}	Customer requested cancellation	Reason recorded at cancellation time.

Undefined variables render as empty string — never undefined or {{variableName}}.

4. Preview before publishing

The detail view shows two read-only fields rendered with sample data:

• Subject preview (sample data) — your subject with example values.
• Body preview (sample data) — your plain-text body with the same example values.

Additional calculated fields warn before publish:

• Rendered subject length — turns red at 78 (NFR-BET-002).
• Body size (bytes) — turns red near 102 KB (NFR-BET-003).
• HTML whitelist valid — false means the body contains a forbidden tag, <script>, <style>, or <link>.

Treat any red indicator as a publish blocker.

5. Publish

When the previews look right and all warnings are clear, choose Publish from the lifecycle actions. Status changes from draft to published and First activated is stamped with the current timestamp.

A published template is immediately active — the next matching booking event dispatches it. Publishing a new version automatically supersedes the previous one for that locale and template type.

6. Archive an obsolete template

When a template is no longer in use:

• Concept archiveren (draft) — never went live; archive directly.
• Archiveren (published) — retire an active template. Dispatched emails remain visible in history; no new dispatches use this template.

Archived templates are terminal — they cannot be reactivated. Clone them to a new draft if you need the content back.

7. Branding customization

Three fields cover most operator branding needs without code or theme changes:

• Logo URL — host the image on a stable CDN or your document store. The email renders the image inline; if the URL fails to load, recipients see the {{organizationName}} text fallback in the surrounding markup.
• Accent colour — pick one hex code; apply it consistently in the HTML body (the seed templates use it for the heading colour).
• Footer text — postal address, contact, legal lines. Free text.

You can use a different logo or colour per template (for example a partner-branded cancellation template). Operators do not need to manage a separate "branding profile" — every template carries its own.

8. Plain-text fallback best practices

Always write the plain-text body — many corporate Outlook installs strip HTML rendering, and accessibility tools prefer plain-text.

• Keep paragraphs short.
• Repeat the booking reference and date clearly.
• Use \n for line breaks (the form input accepts them as Enter).
• Never put critical information in the HTML body only.

9. Email client rendering tips

Email rendering varies wildly. Stay defensive:

• Inline styles only. No <style> blocks. No external CSS via <link>.
• Avoid CSS floats. Use <table> for layout if a column structure is needed.
• Keep images small and host them on a CDN — Gmail caches images via proxy, so they need to be publicly reachable.
• Test in Gmail (web + mobile app), Outlook (web + desktop), Apple Mail, Thunderbird, iOS Mail and the Gmail app before publishing a new template — the QA test plan lists this matrix.
• Don't rely on background images.
• Sub-7 KB HTML bodies render best across the spectrum (the 102 KB ceiling is the hard SMTP/anti-spam limit, not a target).

10. Permissions

Permission slug	Role
booking:template:list	template-administrator, booking-administrator, auditor
booking:template:create	template-administrator
booking:template:edit	template-administrator, booking-administrator
booking:template:publish	template-administrator, booking-administrator
booking:template:delete	template-administrator

auditor is read-only.

11. Version management

The draft → published → archived lifecycle gives operators a simple versioning workflow:

1. Clone a published template to draft. The clone is independent — edit text and branding freely.
2. Publish the new version. The previous version is automatically superseded for that locale and template type — no dispatches use it anymore.
3. Archive the old version when you are confident the new one works. The history of dispatched emails using the old version stays queryable.

There is no scheduled-rollout feature in this release; publish takes effect immediately.

Troubleshooting

Symptom	Likely cause	Action
"HTML whitelist valid" is false	Body contains <style>, <script>, <link> or an unsupported tag.	Remove the disallowed element; use inline styles only.
Subject is truncated in inbox	Rendered length exceeds 78 characters.	Shorten the static text — variable substitutions can push real subjects past the warning.
Variable shows as {{customerName}} literally in the email	Typo in variable name — {{Customer Name}} (with space) is undefined.	Match the case-sensitive variable list above exactly.
Logo not visible to recipients	Logo URL not publicly reachable, or Gmail's image proxy blocked it.	Host the logo on a public CDN or your document-store; do not use inline base64.
Reminder didn't fire	Reminder template is draft, the booking system event has not fired, or the dispatch window was missed by more than the tolerance.	Confirm the reminder is published; check the booking schedule and the notification engine logs.
Cancellation email has empty {{cancellationReason}}	"Include cancellation reason" was off at cancellation time, or the booking system did not record a reason.	Toggle the flag on; verify the booking-cancellation flow records the reason.

See also

• SMS Reminder Channels — multi-channel companion surface for reminders.
• Booking Templates API contract — developer-facing template dispatch contract.