OpenCart 1.5: what to do with an old shop

In short: it is not a version to leave without a plan, even if the shop runs without errors. The last official 1.5 release is 1.5.6.4, from 2014. The OpenCart code repository has no newer 1.5 release, so do not expect official fixes for it.

The 1.5.6.4 installer requires the PHP extensions mysql and mcrypt. According to php.net, mysql was removed in PHP 7.0 and mcrypt in PHP 7.2. So, without extra patches, a 1.5 shop runs only on old PHP versions that the PHP project no longer supports. As of 25 October 2026, php.net lists PHP 8.2–8.5 as supported.

That does not mean your shop has been compromised, only that no official fix should be expected if a new vulnerability appears. The practical risk is the hosting provider switching off the old PHP: the shop may then show an error or a blank page.

Find out these five things before you decide.

1. Version. The OpenCart version number is shown at the bottom of the admin panel, for example 1.5.6.4.
2. PHP version. Find it in the hosting control panel or ask the provider, and ask whether old versions will be switched off.
3. Extensions. List the installed extensions (modules): which were bought, which were written specially for your shop, and whether their developer is still reachable.
4. Theme. Default, bought or customised? That decides whether it must be rebuilt.
5. Backup. Have a backup of all files and the database, kept somewhere other than the same server.

Go through the questions in order and stop at the first one that gives you an answer.

1. Does the shop work, and does the hosting provider still offer a PHP version it runs on?
   • Yes. You can leave it for now: install no new extensions, keep making backups and set a date to review.
   • No, or the provider is already changing PHP. Go to question 2.
2. Are there few extensions, and is the theme standard or simple?
   • Yes. Moving to OpenCart 3.0.x is a realistic option.
   • No, there are many extensions or the core code was modified. Read “When a move is too complex”.
3. Is the problem only the look, for example text that is hard to read and tap on a phone?
   • If the system works, the look can be updated on the old version too; the PHP question remains but can wait.

Between 1.5 and 3.0 there is another major version, 2.x. The official 3.0.x upgrade guide covers only 2.x and 3.x, and for 1.5.x it suggests trying OpenCart’s support team. So OpenCart 1.5 to 3.0 is not a one-button upgrade. The main differences:

• Theme. OpenCart 3.0 uses Twig instead of the old .tpl templates, so a 1.5 theme will not work and has to be rebuilt.
• Extensions. OpenCart’s own versioning rules say a major version change would likely break most third-party modules. Some need new versions, others must be replaced, and old vQmod files may need updating.
• Page addresses. Version 3.0 stores them in a different database table (seo_url instead of url_alias), so old addresses must be moved and checked.
• Database. The table structure has changed, so products, customers and orders are moved and checked separately.

So I carry out the migration in a test copy: I move the data to OpenCart 3.0.x, rebuild the theme, adapt or replace the extensions and check the addresses, while your shop keeps running. The steps are on the OpenCart upgrade page.

The latest OpenCart 3.0.x releases, 3.0.5.1 (August 2026) and 3.0.5.0, require PHP 8.1 or newer; the earlier 3.0.4.1, 3.0.4.0 and 3.0.3.9 require PHP 7.3 or newer. So your hosting provider must offer a suitable PHP version. Each extension must be checked separately: meeting the system requirement does not mean your extensions will work.

A move takes more work than it is worth when:

• many extensions are installed, especially ones written for your shop by a developer who is gone;
• the core OpenCart files were changed, not just extended;
• the theme is heavily customised or no longer supported;
• nobody knows what was changed in the shop.

In that case I first establish with you what must be kept. Some extensions may have to be replaced or dropped; I will tell you in advance.

OpenCart 4.x is yet another major version. The official 3.x to 4.x documentation says to check extension and theme compatibility with OpenCart 4 before upgrading, and that PHP must be 8.0 or newer. My suggestion is OpenCart 3.0.x. Whether OpenCart 4 would suit your shop, I can assess after the check, because it depends on your theme and extensions.

e.segris.lt. It was an old OpenCart 1.5 shop. I gave it a new look for phones and computers and set up the secure connection (SSL, HTTPS). Moving to a newer OpenCart version is a separate job. Screenshots are in “Past work”.

If you have decided to move, my way of working is on the OpenCart upgrade page. If the shop shows an error after a PHP change, see the Fixing website errors page. After the move you can choose monthly website maintenance.