# Flash Sale & Countdown — Complete Guide

> Overview and requirements Flash Sale turns your promotions into genuine time-limited flash sales. You schedule a campaign over a date window; the module applies the discount automatically through PrestaShop native…

- Page: <https://www.datafirefly.com/en/documentation/dfflashsale/>
- Language: en
- Last updated: 2026-10-01
- Other languages: [fr](https://www.datafirefly.com/documentation/dfflashsale/index.md), [es](https://www.datafirefly.com/es/documentation/dfflashsale/index.md), [de](https://www.datafirefly.com/de/documentation/dfflashsale/index.md), [it](https://www.datafirefly.com/it/documentation/dfflashsale/index.md), [pl](https://www.datafirefly.com/pl/documentation/dfflashsale/index.md), [pt](https://www.datafirefly.com/pt/documentation/dfflashsale/index.md), [nl](https://www.datafirefly.com/nl/documentation/dfflashsale/index.md)
- Index: <https://www.datafirefly.com/en/documentation/llms.txt>

## Overview and requirements

Flash Sale turns your promotions into genuine time-limited flash sales. You schedule a campaign over a date window; the module applies the discount automatically through PrestaShop native specific prices and shows a countdown synced to server time. The promotional price therefore applies everywhere (product page, listings, cart and emails), with no change to your theme.

- Compatible with PrestaShop 8.0 to 9.x, Classic theme and derived themes.
- PHP 7.4 to 8.3.
- Multistore and multilingual (FR/EN/ES/DE/IT/PL/NL/PT).
- No CRON task required: the discount is switched on and off by the specific price dates.
- PrestaShop-compliant architecture (ModuleAdminController, ObjectModel), PSR-4 autoloader with no Composer dependency.

The discount is pushed into a **specific price** whose `from` / `to` window matches the campaign dates. PrestaShop activates and removes it on its own, to the second.

## Installation

Install the module like any PrestaShop module:

1. Download the `dfflashsale.zip` archive from your customer account.
2. In the back office, go to **Modules > Module Manager**.
3. Click **Upload a module** and drop the archive.
4. Once installed, manage your campaigns from **Catalog > Flash Sales**.

On installation the module creates its tables (campaigns, targeting, specific-price mapping), registers its display hooks and adds the **Flash Sales** tab under Catalog.

## Global module settings

The configuration page (**Configure** from the Module Manager) gathers the global settings shared by all campaigns:

- **Sync the countdown to the server**: aligns the clock to server time (recommended). See the dedicated section.
- **Offset page content (push body)**: automatically adds a margin so the sticky banner never overlaps content.
- **Show the banner on mobile**: shows or hides the banner on small screens.
- **Banner z-index**: the banner stacking level, to raise if a theme element appears on top of it.

## Creating a flash-sale campaign

From the **Catalog > Flash Sales** tab, click **Add a campaign**. The form is organised into panels.

### General

- **Name**: internal identifier of the campaign (free text).
- **Active**: enables or suspends the campaign.
- **Start / end date**: the activity window. The discount and the countdown rely on these dates.
- **Priority**: if several campaigns target the same product, the one with the highest priority wins for display.
- **Shops**: in multistore, select the relevant shops.

### Discount

- **Discount type**: **Percentage** (e.g. -30%) or **Fixed amount** (e.g. -€15).
- **Value**: the percentage or amount of the discount.
- **Currency**: for a fixed-amount discount, the reference currency.
- **Tax**: indicates whether the fixed amount is tax included or excluded.

The discount is applied through specific prices: it combines with PrestaShop native price rules according to their priority, and shows from the cart onwards.

### Targeting

Choose the scope of the campaign:

- **Whole catalog**: the discount applies to every product.
- **Categories**: select one or more categories. The **Include subcategories** option extends the discount to the whole tree.
- **Products**: search and select specific products (by name, reference or ID).
- **Brands**: select one or more manufacturers. All of their products are included automatically, including those added after the campaign was created.

### Display

- **Countdown banner**: shows the global promo bar.
- **Banner position**: top or bottom of the page.
- **Sticky banner**: keeps the banner visible while scrolling.
- **Show on product pages**: adds a countdown card under the price.
- **Show on home**: adds a promotional block on the home page.
- **Badge on product images**: shows the campaign name over the photo, in listings and on the product page.
- **Teaser before start**: shows a "starts in…" countdown before the start date.
- **When the countdown ends**: hide the element or show an end message.

### Appearance and copy

The **Appearance** panel sets the background colour, the text colour and the accent colour, plus the call-to-action (CTA) button link. The **Copy** panel gathers the translatable labels: banner title and subtitle, button text and end message, editable for every shop language.

## How scheduling works

When you save a campaign, the module creates the specific prices matching the targeting: a global specific price (product 0) for "whole catalog", or one specific price per product for category and product targeting. Each specific price's validity window is aligned to the campaign start and end dates.

PrestaShop therefore turns the discount on and off by itself, to the second, with no scheduled task. The IDs of the created specific prices are stored in a mapping table so they are removed cleanly when the campaign is edited, deleted or the module is uninstalled.

For category targeting with subcategories, the product list is resolved at save time by walking the tree (nleft / nright). Remember to re-save the campaign if you reorganise your categories.

## The server-synced countdown

The countdown is aligned to server time, not the visitor's. At render, the module passes the server timestamp and the end date; the script computes an offset between server time and local time, then counts down locally from that offset.

As a result, a visitor who moves their computer clock forward or back does not skew the timer. No repeated network call is needed, and the countdown stays smooth and accurate for everyone.

You can disable server sync in the global settings; the countdown then relies on the browser's local time.

## The badge on product images

The **Badge on product images** option shows the promotion name directly on the product image, both in category listings and on the product page. It is the right tool to flag a named operation visually, for example BLACK FRIDAY.

The label is entered in the **Copy** panel, field **Product badge text**, for each language. If left empty, the module falls back to the banner title. The badge colour is the accent colour defined on the campaign.

Technically the badge is added to PrestaShop native _flags_, the ones already used for the "New" or "-30%" labels. It is therefore positioned and styled by your theme, with no template override.

The badge only shows while the campaign is running. In teaser mode, before the start date, it stays hidden so you never announce a discount that is not applied yet.

## Banner display area and size

Since version 1.2.0, two settings in the **Display** panel control where the banner appears and how much space it takes. They are set per campaign.

### Show the banner on

- **Whole site**: the banner shows on every page. This is the default, kept for campaigns created before 1.2.0.
- **Pages covered by the promotion**: pages of the targeted products and pages of the targeted categories or brands. A whole-catalog campaign stays visible everywhere.
- **Promoted product pages only**: the banner only appears on the page of a product covered by the campaign.

On a page where the top-priority campaign is not allowed, the module moves on to the next campaign by priority. You can therefore reserve one banner for a brand and keep a generic banner on the rest of the site.

For a campaign targeting products, the "Pages covered" area is limited to those product pages: category pages that contain them do not show the banner.

### Banner size

- **Standard**: title, subtitle and countdown with labels (Days, Hours, Min, Sec). About 56 px high on desktop.
- **Compact**: countdown without labels, formatted as `2d 14:05:33`. About 35 px on desktop and 55 px on mobile, against 128 px in Standard.
- **Mini (single line)**: a one-line strip of about 26 px, subtitle hidden and title truncated when space runs out. The most discreet format on mobile.

In Compact and Mini, the days unit disappears when less than 24 hours remain.

## Evergreen mode

**Evergreen** mode turns the campaign into an individual perpetual timer: each visitor gets their own deadline, triggered on their first visit and based on a duration in minutes that you define. The deadline is kept locally (localStorage) so it stays consistent across pages and visits.

In evergreen mode the countdown is unique to each visitor and does not match the real discount window. Use it for personalised urgency messages rather than to signal a shared promotion end.

## Multilingual and multistore

All labels (title, subtitle, button, end message) are translatable per language. In multistore, each campaign can be restricted to specific shops, and specific prices are created per shop. A single campaign can therefore target one shop without affecting the others.

## FAQ and troubleshooting

### The discount does not apply

Check that the campaign is **active**, that today's date is within the start and end dates, and that it concerns the current shop. For category targeting, make sure you re-saved the campaign after any reorganisation of the tree.

### The banner overlaps my menu or content

Enable the **Offset page content (push body)** option in the global settings. If a theme element appears above the banner, raise the **z-index** value.

### The countdown shows an inconsistent time

Make sure your server time is correct and that server sync is enabled. The timer aligns to server time, regardless of the visitor's clock.

### Several campaigns target the same product

Display keeps the campaign with the highest **priority**. For the discount, PrestaShop's specific-price priority logic applies.

### The badge does not show on the photos

First check that the **Badge on product images** option is enabled on the campaign and that the start date has passed. If the badge is still missing after clearing the cache, open the module configuration page or the **Catalog > Flash Sales** tab: the module then checks its hooks and registers any that are missing. This happens after an update made by simply replacing files, which does not run the upgrade script.

### What happens on uninstall?

Uninstalling removes every specific price created by the module via its mapping table, deletes its hooks and tab, and cleans up its tables. Your original prices are fully restored.