Display installment plans in 1C-Bitrix product card

Not having an installment plan block in the product card means that a customer sees a price of 150,000 RUB and leaves. Our analytics show that up to 30% of sessions break off at the payment method selection stage. Backed by 10 years of Bitrix development experience, we guarantee stability and calculation accuracy. Our 1C-Bitrix component displays available plans with bank logos and monthly payment calculation — right in the product card. The solution works on any tariff and scales.

Problems solved by the installment block

• Lack of information for the customer. A product costs 10,000–200,000 RUB but the possibility of paying in installments is not shown — the visitor thinks it is not available. The component displays available plans with bank logos and contribution amounts.
• Conversion drop. According to our projects' data, BNPL presence increases average order value by 20–30%. Customers choose more expensive items knowing they will pay in installments.
• Calculation errors. Manual amortization calculation leads to inconsistencies with the bank. We automate the annuity payment formula and verify it on test data.

Implementation of displaying installment terms

We use an HL-block InstallmentPlans to store fixed terms (partner, rate, periods). For dynamic terms, we connect bank APIs via cached requests. The PHP calculation code is duplicated in JavaScript for client interactivity.

Storing terms in HL-block

Calculating monthly payment

For interest-free: monthly = price / months. For interest-bearing — annuity formula. PHP function:

function calcInstallment(float $price, int $months, float $annualRate): float {
    if ($annualRate <= 0) {
        return $price / $months;
    }
    $r = $annualRate / 12 / 100;
    return $price * $r / (1 - pow(1 + $r, -$months));
}

JavaScript counterpart for recalculation when selecting a period:

function calcInstallment(price, months, annualRate) {
    if (annualRate <= 0) return price / months;
    const r = annualRate / 12 / 100;
    return price * r / (1 - Math.pow(1 + r, -months));
}

We attach handlers to period selection buttons. Each partner is displayed with a logo and month buttons. The minimum payment is shown for the longest period.

Displaying the block in the product card

In the catalog.element template, after the price, we load matching plans:

$price = (float)$arResult['CATALOG_PRICE_1'];
$plans = \Local\Installment\InstallmentPlanTable::getList([
    'filter' => ['=UF_ACTIVE' => true, '<=UF_MIN_AMOUNT' => $price],
    'order' => ['UF_MIN_AMOUNT' => 'ASC'],
])->fetchAll();

On the frontend, for each partner we render a block with logo and period selection buttons. On click, the monthly installment updates.

Caching API requests: criticality and approach

Each card opening without cache generates an HTTP request to the bank. With 10,000 card views per day — that's 10,000 requests. Caching reduces them to the first few within 10 minutes. We use Bitrix tagged caching to invalidate cache when partner terms change. The 1C-Bitrix documentation recommends this approach for high-load projects.

Caching makes the installment block 100 times more efficient in terms of server load.

What is included in the work

1. Requirements analysis — determine term sources (static/API), agree on block design.
2. HL-block and component development — create storage, write output component.
3. Calculation logic integration — implement PHP and JS functions, test on edge values.
4. Bank API integration — connect, configure caching, handle errors.
5. Layout and styling — adapt block to site design, add legal texts.
6. Testing and deployment — test on all devices, record results.
7. Documentation and training transfer — describe setup, provide manager instructions.

Typical setup errors

• Not considering the minimum product threshold. If the amount is below UF_MIN_AMOUNT, the block is not shown — the customer sees nothing. We should also display a placeholder or message.
• Forgetting recalculation when price changes. If the page has option selection, the price changes — the installment must update. We use the event BX.addCustomEvent('onCatalogPriceChange').
• Not including legal text. According to 54-FZ, it is mandatory to display that the installment is provided by the partner bank. We add it below the block.

Indicative timelines

Cost is calculated individually depending on the number of partners and API complexity.

If you already have agreements with banks or want to connect BNPL services — we will evaluate your project and offer a solution. Contact us for a consultation. Order customization of installment plan display in the 1C-Bitrix product card.

What Professional 1C-Bitrix Installation Includes

We start by checking innodb_buffer_pool_size. The default MySQL value (128 MB) is a death sentence for an online store with a catalog of 10,000+ items. We set 70–80% of available RAM on a dedicated server, 50% on VPS. This single setting speeds up the site by 2–3 times compared to the default. We'll assess your project in one day — get a consultation. Contact us to order turnkey installation with performance guarantee.

How to Choose Hosting and Edition for 1C-Bitrix Installation?

BitrixVM is a virtual machine with a pre-installed stack: nginx + Apache, PHP-FPM, MySQL/MariaDB, Sphinx, Push server. For VPS — the best start. Everything is already configured for Bitrix, including OPcache, log rotation, and firewall. Management via web panel on port 8890. Bitrix documentation recommends starting with BitrixVM for predictable performance.

VPS/VDS is the sweet spot. Minimum configuration for a medium online store: 2 vCPU, 4 GB RAM, SSD. Optimal: 4 vCPU, 8 GB RAM. OS: Ubuntu 22.04 or Debian 12. If not BitrixVM, we configure the stack manually for the task. Virtual hosting — only for business cards and landing pages. Requirements: PHP 8.0+, MySQL 5.7+ / MariaDB 10.0+, 512 MB RAM, .htaccess. 1C-Bitrix hosting partners guarantee compatibility. Dedicated server — for highload. Typical architecture: web server separate, database separate, Redis/Memcached separate. For Enterprise edition — web cluster with load balancer. Cloud (Yandex Cloud, VK Cloud, Selectel) — when load spikes: sales, seasonal peaks. Autoscaling via Managed Kubernetes or simple VM vertical scaling.

Choosing the edition is equally important. A common mistake: choosing "Small Business" for a store that grows to B2B with wholesale prices and three warehouses in six months. Upgrading to "Business" — pay the difference, data is not lost, but it's better to plan ahead. Our specialists select the edition for current tasks and with room for growth. For example, the "Business" license (about 35,000 RUB) pays off through multi-warehouse and 1C exchange, while the wrong choice can lead to a loss of up to 30,000 RUB monthly on excess resources.

What Server Settings Are Critical for 1C-Bitrix?

Web Server and PHP

nginx as reverse proxy + Apache (mod_php) or nginx + PHP-FPM directly. The second option saves memory — Apache is not needed. But some Bitrix modules use .htaccess, so for compatibility we sometimes keep Apache. nginx configuration: fastcgi_read_timeout 300 — for long operations (1C import), client_max_body_size 1024m — large file uploads. Block access to .settings.php, .settings_extra.php, bitrix/.settings.php — they contain database passwords. Rewrite rules from urlrewrite.php — Bitrix generates them, but with nginx + PHP-FPM they need to be duplicated. PHP 8.0–8.2 with extensions: mbstring, curl, gd, xml, json, opcache, redis/memcached. Key php.ini settings: opcache.memory_consumption=256, opcache.max_accelerated_files=20000, max_execution_time=300, memory_limit=512M, upload_max_filesize=100M, post_max_size=128M.

Database and Caching

MySQL/MariaDB. Key my.cnf parameters: innodb_buffer_pool_size — 70–80% RAM, innodb_log_file_size=256M, tmp_table_size=256M, max_heap_table_size=256M, thread_pool_size — number of CPU cores. Encoding utf8mb4 mandatory, otherwise emoji and special characters break. Redis is preferable to Memcached for Bitrix — supports persistent connections and is more reliable. In production, Redis handles concurrent writes three times faster than Memcached under typical load. Configure in .settings_extra.php:

'cache' => ['value' => ['type' => ['class_name' => '\\Bitrix\\Main\\Data\\CacheEngineRedis']]]
'session' => ['value' => ['mode' => 'default', 'handlers' => ['general' => ['type' => 'redis']]]]

sudo apt install redis-server
sudo systemctl enable redis

SSL, Email, and Cron

SSL — Let's Encrypt via certbot in 90% of cases. Redirect HTTP → HTTPS (301), HSTS, TLS 1.2/1.3, OCSP Stapling. In Bitrix, switch to HTTPS in the main module settings. Email: abandon mail() — connect SMTP (Yandex.Mail for domain, Mail.ru for Business). Be sure to configure SPF, DKIM, DMARC. Without SPF, emails go to spam. Test deliverability via mail-tester.com — score 9+/10. Cron: Bitrix agents switch to system cron — * * * * * /usr/bin/php /var/www/bitrix/modules/main/tools/cron_events.php. Schedule 1C exchange (15–60 min), search reindex, backups (mysqldump + rsync, rotation 7+4), temporary file cleanup.

Security and Administration

File system: owner www-data, directories 755, files 644, upload 775. nginx blocks access to configuration files. Enable Bitrix Proactive Protection — WAF, activity control (block after 5 failed attempts), kernel integrity check. For admin panel: two-factor authentication via Google Authenticator or OTP, restrict access by IP via nginx for paranoid.

How Long Does 1C-Bitrix Installation and Configuration Take?

Post-Installation Checklist

1. Performance Monitor (/bitrix/admin/perfmon_panel.php) — aim for 30+ points. Below 20 means serious configuration issues.
2. System Check — automatic check of all parameters. Red items must be fixed, yellow — case by case.
3. Security Scanner — check for typical vulnerabilities.
4. PageSpeed Insights — TTFB < 200ms on VPS, LCP < 2.5s.
5. Test 1C exchange — if integration is planned, verify CommerceML exchange before launch.

Additionally, check software versions, caching settings, cron operation, SSL certificate, SPF/DKIM/DMARC, access rights, delete default users and pages. For projects with 54-FZ, ensure fiscalization is configured via OFD provider.

Deliverables

• Fully configured server for 1C-Bitrix with MySQL, PHP, nginx optimization.
• Installed and activated license of the required edition.
• SSL certificate, email settings, cron and backups.
• Documentation: all configuration parameters, access credentials, cron tasks.
• Content manager training: how to log into admin panel, add products, upload images.
• Post-installation support for 30 days — consultations on settings.

Why Trust Professionals with Installation?

Incorrect installation means lost time and money. We've seen projects where a store on "Start" couldn't handle 50 visitors because innodb_buffer_pool_size wasn't configured. After migrating to VPS with correct configuration, the site "flew". Incorrect configuration can cost 30,000 RUB monthly due to excessive resource consumption. You get a ready-made architecture that scales. Order turnkey 1C-Bitrix installation — get a reliable platform for business growth. Contact us for a free consultation: we'll calculate the cost and time for your project. Over 7 years of experience, 120+ Bitrix projects implemented, including highload stores with million-item catalogs. Get in touch — we'll help configure Bitrix for your project.