Pro · Professional planRequires Easy Invoice Pro with a Professional (or Agency) license.

Smart Reminders & Late Fees

A multi-step dunning workflow on top of the basic "X days before due" reminder that already ships in Pro. Add steps, customize the email template per step, auto-apply a late fee after N days overdue, and optionally offer an early-payment discount.

When to use it

• You're losing cashflow to overdue invoices
• You don't have time to manually chase clients
• You want fees / discounts handled consistently across every invoice

The single highest-ROI feature in the Pro plan. Typical recovery on previously-written-off invoices is 15–25% in the first month.

How it differs from the built-in reminder

Easy Invoice Pro already ships a basic "remind me X days before due date" feature. Smart Reminders adds three things that don't exist in core:

Feature	Core reminder	Smart Reminders addon
Steps	1 (pre-due only)	Unlimited (pre + post due)
Per-step email template	No	Yes
Auto-apply late fee	No	Yes (% or flat)
Early-payment discount	No	Yes
"Run now" button	No	Yes
Per-invoice progress tracking	No	Yes (last step + late-fee flags)

You can run both simultaneously — they don't conflict on cron hook names or meta keys.

Enabling

1. Easy Invoice → Addons
2. Find Smart Reminders & Late Fees
3. Click Activate
4. Open via the Settings → link or navigate to Easy Invoice → (sidebar) → Smart Reminders (slug: easy-invoice-addon-dunning)

The addon registers one daily WP-Cron event: easy_invoice_dunning_daily_tick.

Configuring the workflow

Reminder Schedule

Each row in the schedule is one step. A step is "send this email to the client when the invoice is X days from its due date." Offset days are relative to the invoice's due date — negative = before, positive = after.

Default schedule shipped with the addon:

Step	Offset	Tone
1	-3 days	"Friendly reminder — your invoice is due in 3 days"
2	+1 day	"Your invoice is overdue"
3	+7 days	"Second notice"
4	+14 days	"Final notice"

Each step has a Subject and a Body with smart-tag interpolation. Available tags:

{{invoice_number}}   {{client_name}}   {{total_amount}}
{{due_date}}         {{invoice_url}}   {{company_name}}

Add as many steps as you want with Add step, reorder by changing offset values (rows are sorted on save). Each step fires exactly once per invoice — the addon records the last-sent step in _easy_invoice_dunning_last_step so a step is never re-sent.

Late Fee

Auto-apply a fee after N days overdue:

Option	Default	What it does
Enable late fees	off	Master switch
Fee type	percent	percent of invoice total, or flat currency amount
Amount	5	Percent (if percent) or flat currency (if flat)
Apply after (days)	7	Days overdue before the fee is calculated and stored

The calculated fee is stored in invoice meta _easy_invoice_late_fee_amount and _easy_invoice_late_fee_applied_at. To surface it on the rendered invoice, the addon hooks two filters automatically:

easy_invoice_calculate_total     ⟶ adds fee to total
easy_invoice_extra_line_items    ⟶ appends fee as a line item

That means the late fee shows up automatically on the invoice — no extra wiring needed.

Early-Payment Discount

Encourage clients to pay before due date:

Option	Default	What it does
Enable discount	off	Master switch
Discount percent (%)	2	Percentage off
Within (days of issue)	7	Pay within N days of the issue date to qualify

The discount is offered in your reminder emails (use a smart-tag in the body) and recorded as discount-related meta when honoured — full automation of discount enforcement requires payment-gateway integration and is on the roadmap.

Running it

Daily cron

The hook easy_invoice_dunning_daily_tick runs once per day. WP-Cron is "pseudo-cron" — it runs on real page loads, so a quiet site may run a day late. If you have real cron set up (wp-cron.php from system cron), the run is exactly on schedule.

"Run now"

The Run now button (top-right of the addon page) calls the same Service::runDailyTick() synchronously. Useful when you've just changed the schedule and want to see immediate results. The redirect shows a banner like:

Dunning run complete. Scanned 247 invoice(s) — sent 12 reminder(s), applied 3 late fee(s).

Behaviour at scale

The tick is designed for thousands of invoices:

• Batched query: invoices are loaded 50 at a time (posts_per_page=50, paged=N). Never posts_per_page=-1.
• SQL-level filter: only invoices whose _easy_invoice_due_date <= today + max_pre_offset_days are loaded — the runner never touches paid invoices, cancelled invoices, or invoices whose first reminder is still weeks away.
• Wall-clock budget: by default 25 seconds. If the runner can't finish the queue in that time, it stops at a batch boundary and the next cron picks up where it left off (per-invoice progress is durable via _easy_invoice_dunning_last_step).
• Per-invoice progress: re-runs are idempotent — a step that already fired for an invoice is skipped.

Filters for tuning:

// How many invoices to load per query (default 50)
add_filter('easy_invoice_dunning_batch_size', fn() => 100);

// How long each tick may run (default 25s)
add_filter('easy_invoice_dunning_tick_budget_seconds', fn() => 45);

Permissions

Anyone with manage_options can use the addon. With Team Members & Audit Log enabled, every reminder send and fee application is logged.

Hooks for developers

Hook	Type	When
easy_invoice_dunning_email_sent (invoice_id, step, recipient_email)	action	Just after a reminder email is wp_mail()'d
easy_invoice_dunning_late_fee_applied (invoice_id, fee, settings)	action	Just after a late fee is stored on an invoice
easy_invoice_dunning_after_tick (reminders_sent, fees_applied, scanned)	action	End of every daily tick
easy_invoice_dunning_batch_size	filter	Override the per-batch invoice count
easy_invoice_dunning_tick_budget_seconds	filter	Override the tick wall-clock budget

Example — Slack notification on every late fee:

add_action('easy_invoice_dunning_late_fee_applied', function ($invoice_id, $fee, $settings) {
    $client = get_post_meta($invoice_id, '_easy_invoice_customer_name', true);
    $msg    = sprintf('Late fee of %.2f applied to invoice #%d (%s)', $fee, $invoice_id, $client);
    wp_remote_post('https://hooks.slack.com/services/…', [
        'body' => wp_json_encode(['text' => $msg]),
    ]);
}, 10, 3);

Smart tag reference

The body and subject of each reminder step support these tags. They're interpolated server-side just before wp_mail():

Tag	Source
	_easy_invoice_number meta, or #{ID} if missing
	_easy_invoice_customer_name meta
	_easy_invoice_total, formatted with 2 decimals
	_easy_invoice_due_date, formatted via the site's date_format
	get_permalink($invoice_id)
	easy_invoice_company_name option

The body is run through nl2br() so plain-text newlines become <br>. HTML in the body is allowed (kept by wp_kses_post on save).

Coexistence with the built-in Pro reminder

The basic Pro reminder uses cron hook easy_invoice_send_payment_reminders and option easy_invoice_payment_reminder_settings. Smart Reminders uses cron hook easy_invoice_dunning_daily_tick and option easy_invoice_dunning_settings. No conflict — but you might double-send if both are configured to email at the same offset. If you've enabled the addon, consider disabling the built-in reminder under Settings → Email → Payment Reminder.

Troubleshooting

"Run now" reports 0 reminders sent

Most common causes:

1. The schedule's offset has no step matching today's today − due_date for any invoice
2. Invoices are missing a _easy_invoice_due_date meta value
3. Invoices are already paid / cancelled / refunded (excluded by design)
4. Each matching step has already been sent for the matching invoice (per _easy_invoice_dunning_last_step meta)

The "Scanned N invoice(s)" count in the banner tells you how many invoices the SQL pre-filter let through — if Scanned is 0, your filter cut everything out (often a missing due date).

Cron isn't firing

WP-Cron only runs when someone visits the site. Add real cron:

*/5 * * * * curl -fsS https://your-site.com/wp-cron.php?doing_wp_cron > /dev/null 2>&1

Then disable WP's built-in cron:

// wp-config.php
define('DISABLE_WP_CRON', true);

See Troubleshooting → WP-Cron.

Late fee doesn't show on invoice

The fee writes to _easy_invoice_late_fee_amount meta and the addon's two filters surface it. If you've replaced the invoice render pipeline with a custom template, you may need to call those filters yourself:

$total = apply_filters('easy_invoice_calculate_total', $base_total, $invoice_id);
$items = apply_filters('easy_invoice_extra_line_items', $items, $invoice_id);

See also

• Email & notifications — base email config the reminders ride on
• Payments — how status flips to paid (which stops dunning)
• Webhooks & Zapier Bridge — fire a webhook when a reminder is sent
• Addons overview