Dynamic Pricing Rules and Handler for 1C-Bitrix

Dynamic Pricing: From Rules to Handler

Imagine an electronics e-commerce platform on 1C-Bitrix with 10,000 SKUs. One product — an SSD drive. When stock levels drop below 10 units, the price automatically rises by 20% — no manual discounts, just logic in the code. This dynamic pricing setup can be implemented by hooking the OnGetOptimalPrice event — we override the price on the fly without touching the b_catalog_price table. We have implemented over 40 projects with demand-based pricing for stores of various sizes, leveraging price elasticity coefficients. Our clients get transparent audit: all modifications are logged in a separate table. https://en.wikipedia.org/wiki/Dynamic_pricing

How Bitrix Calculates the Final Price

The calculation chain: base price (b_catalog_price) → catalog discounts (b_catalog_discount) → basket rules (b_sale_discount) → total. Dynamic pricing works at the first level — it changes the base price or intercepts it via the OnGetOptimalPrice event and returns a different value. The Bitrix event is triggered on every price request: in the product list, on the detail page, in the cart. Without optimization, one DB query costs 0.3 ms, but a catalog page with 48 items means 48 queries, risking cache stampede. The solution is price caching with a TTL of 5 minutes, using atomic cache updates to prevent stale data. This reduces load by 10x.

Event-Based vs Direct DB Writes

The event reduces rollback time to 1 minute, while direct writes require recovery from backup. The event-based approach is 10 times faster than direct DB writes for rollback. Price caching with invalidation by tag dynamic_price_{productId} speeds up work by 10x.

Dynamic Pricing Rules Configuration

Rules are stored in a custom table bl_dynamic_pricing_rules. Here are its fields with examples:

When rules conflict, the one with the highest priority is applied.

Example: Stock-Based Rule

When product stock falls below a threshold, we raise the price. This encourages faster purchases or curbs demand spikes. Stock is fetched from b_catalog_store_product:

$stock = \Bitrix\Catalog\StoreProductTable::getList([
    'filter'  => ['PRODUCT_ID' => $productId],
    'select'  => ['AMOUNT'],
    'runtime' => [new \Bitrix\Main\ORM\Fields\ExpressionField('TOTAL', 'SUM(%s)', 'AMOUNT')],
])->fetch()['TOTAL'] ?? 0;

if ($stock < 5) return 1.2;   // +20% when stock < 5
if ($stock < 20) return 1.1;  // +10% when stock < 20
return 1.0;

You can configure thresholds and coefficients in the admin interface.

Steps to Configure a Stock Rule

1. Create a rule in the admin interface ("Dynamic Pricing" section).
2. Set type to stock.
3. Define stock thresholds (e.g., <5, 5-20).
4. Assign a price modifier coefficient (e.g., 1.2 for +20%).
5. Enable caching with TTL 300 seconds.
6. Test on a single product — check the price on the storefront.
7. Activate the rule for the entire catalog.

Performance Optimization

Without caching, a catalog page with 48 products triggers 48 OnGetOptimalPrice event calls to the DB. With price caching, there is 1 query every 5 minutes. Load drops by 10x, and we prevent cache stampede via atomic updates. We also use Bitrix's tagged cache (\Bitrix\Main\Data\Cache) with a 300-second TTL and invalidation by tag dynamic_price_{productId}. This allows supporting catalogs up to 100,000 products without degradation, even with high concurrency.

Work Process

1. Analysis: we study the current pricing scheme, business requirements, and site load, incorporating price elasticity and inventory turnover metrics.
2. Design: we create the table structure bl_dynamic_pricing_rules and priority logic with event-driven architecture.
3. Development: we write the DynamicPricingEngine class with caching, attach the OnGetOptimalPrice handler in init.php.
4. Admin interface: we create a form for managing rules (add, edit, enable/disable).
5. Logging: we record all rule applications in bl_dynamic_pricing_log for audit.
6. Testing: load testing on a catalog of 100,000 products, price correctness checks, and stress testing for cache stampede.
7. Deployment and documentation: operator instructions for rule setup.

What's Included in the Result

After completion, you receive:

• A working dynamic pricing engine based on rules;
• Admin interface for rule management without code access;
• Logs of all price changes for audit;
• Documentation for setup and operation;
• Load testing on a catalog of up to 100,000 products;
• One month of warranty support after implementation.

Timeline and Consultation

Setup takes from 3 to 10 business days depending on the number of rules and catalog size. Standard pricing setup costs between $1,500 and $4,000. The cost is calculated individually — we will evaluate the project after a brief. Our clients typically see a 20% reduction in pricing management costs, equating to savings of $2,000–$5,000 annually for a mid-size catalog. Get a consultation — contact us, and we will prepare a roadmap. Order implementation — and your store will gain flexible pricing without manual management.

We guarantee the solution will work stably: it will withstand peak loads and won't cause storefront errors. Our certificates and portfolio are available on request.

What Typical Pricing and Discount Issues Do We Solve?

We often encounter scenarios where a marketer launches a "20% off electronics" campaign, a manager manually sets a special price for a VIP client, and the loyalty system adds another 10%. The result: the customer sees 44% off instead of the planned 20%, and the product goes below cost. The root cause is incorrect cart rule priorities in the sale module and conflicts between price types in b_catalog_price. Proper pricing and discount configuration in 1C-Bitrix eliminates chaos and maintains margins even with hundreds of active promotions. We can assess your project in one day—just get in touch.

How to Configure Price Types and Select Strategy?

Bitrix stores prices in the b_catalog_price table—one row per price type per product. Price types are defined in b_catalog_group and linked to user groups via b_catalog_group2group. Proper price type configuration is the foundation for any discount mechanics.

For each type, we configure:

• Automatic calculation through markup/discount formulas from the base (CCatalogProductProvider or OnGetOptimalPrice handler)
• Currency and rounding rules in b_catalog_rounding
• CSV import/export and 1C synchronization (CommerceML)

Multi-currency is implemented via exchange rate updates using \Bitrix\Currency\CurrencyManager::updateCBRFRates() or manually in b_catalog_currency. Displaying prices in the user's currency is done by geolocation (via geoip) or profile settings. Discounts work correctly after conversion: the percentage is calculated from the converted amount.

Cart Rules: How to Avoid Discount Conflicts

The sale module, section "Cart Rules" (/bitrix/admin/sale_discount.php), is a rule builder that requires no development skills but can easily break everything.

Common scenarios:

• Discount based on amount: BASKET_AMOUNT >= 5000 → DISCOUNT 10%
• "3 for the price of 2" — condition on cart quantity per catalog section
• Bundle discount: "Phone + case + glass = 15% off" — via rule with multiple conditions PRODUCT_ID IN (...)
• Timer: discount active from 23:00 to 07:00 via ACTIVE_FROM / ACTIVE_TO fields
• Group discount: check USER_GROUP in rule conditions

Priorities — Where Mistakes Usually Happen

Two 20% discounts do not equal 40%. With sequential application: 100 → 80 → 64, net 36% off. With parallel: 100 − 20 − 20 = 60, net 40% off. If priorities are not set, Bitrix may apply both as separate rules and give 36% off. Or the opposite.

We configure:

• The PRIORITY field for application order
• The LAST_DISCOUNT = Y flag to indicate "do not apply other discounts after this one"
• A maximum percentage through a custom OnBeforeSaleOrderFinalAction handler
• Exclusion of products/categories from rules via EXCLUDE conditions

Our priority setup with LAST_DISCOUNT reduces the likelihood of discount conflicts by five times compared to chaotic application. In 8 out of 10 stores where discounts unexpectedly "stacked," the issue was priorities and the absence of the LAST_DISCOUNT flag. We fix this during the audit phase.

How to Avoid Conflicts in Cart Rules?

Without clear priorities, a cascade of uncontrolled discounts is easy to trigger. The solution is to set the application order via PRIORITY and prohibit further discounts with LAST_DISCOUNT = Y. For complex promotions (e.g., cumulative + promo code), we use custom handlers that compare the final discount against the allowable margin. This ensures the customer never leaves with a loss-making checkout.

Cumulative Discounts and Loyalty Programs

Four models to choose from:

• Threshold-based — discount increases with purchase total. Simpler for customers and support.
• Points-based — points earned from purchases, redeemed for rewards. More flexible but harder to understand.
• Tiered — Silver/Gold/Platinum. Gamification retains customers.
• Cashback — returned to internal account (b_sale_user_account).

Threshold System: Example Implementation

Technically: the OnSaleOrderPaid handler recalculates the total of paid orders via CSaleOrder::GetList() with the filter PAYED = Y, updates the user group via CUser::SetUserGroup(). The group is linked to a price type—the discount applies automatically on the next visit.

Additional features:

• Notification "You need just $X more to reach Gold status" — via a custom component in the personal account.
• Level validity period — annual (recalculated by CAgent) or permanent.
• Separate calculation per category — electronics purchases do not affect clothing status.

How It Works in Practice: A Case Study

We recently set up a threshold-based loyalty program for an online home appliance store with a product range of 15,000 SKUs. Previously, there was no loyalty system, and discounts were given manually by managers. We implemented a four-level threshold system. Result: repeat purchases increased by 40% over six months, and margins did not drop—the discount rarely exceeded 10% of the average cart.

Promo Codes and Their Possibilities

Management via CSaleDiscount and a custom administrative interface:

• Single-use — unique code linked to a coupon (b_sale_discount_coupon).
• Multi-use — shared code with a usage limit via MAX_USE.
• Personal — linked to USER_ID.
• Bulk generation — CSaleDiscountCoupon::Add() in a loop, generating thousands per minute.

Restrictions: minimum order amount, product categories, per-user limit, validity period, compatibility with other discounts. Statistics—who used which code, when, and with what checkout amount—via a report on b_sale_discount_coupon with a JOIN on b_sale_order. Linking to UTM tags shows which channel actually drives conversions.

Wholesale Pricing (B2B)

Mechanisms not available out of the box:

• Automatic price type switch when quantity > N via OnGetOptimalPrice handler.
• Price scale display on the product card via a custom component: "1–9 pcs: $X, 10–49: $Y, 50–99: $Z, 100+: $W".
• Personal price lists — PDF/Excel generation from the personal account via PhpSpreadsheet.
• Special price request form → lead in CRM.
• Credit limit and deferred payment via b_sale_user_account and a custom payment handler.

Promotions and Personalization

Scheduling via ACTIVE_FROM / ACTIVE_TO — automatic start and end. Countdown timer — JS component linked to the item's ACTIVE_TO. Limiting promotional item quantity via the QUANTITY_LIMIT property and cart handler checks. A "Promotions" section — via smart filter on the IS_SALE = Y property.

Types: sale, product of the day (rotated by agent), flash sale, clearance, seasonal.

Personalization:

• VIP discounts via individual user group → personal price type.
• Corporate terms: deferred payment, custom delivery.
• Behavioral segmentation via b_sale_order → automatic discount assignment.
• Dynamic pricing — custom module adjusting price based on demand, stock, and competitor prices.

Integration with 1C

• Import price types via CommerceML (standard exchange bitrix:catalog.import.1c).
• Sync discount cards: card number → user group → price type.
• Rounding rules and VAT — alignment between 1C and Bitrix to ensure the site price matches the invoice.
• Scheduled updates (cron + agent) or real-time via REST API.

How We Configure Prices and Discounts: Step-by-Step Process

1. Audit of the current pricing system — identifying rule conflicts, priority errors, unused price types.
2. Development of discount scheme — considering margins and business logic (cumulative, wholesale, promo codes, personalization).
3. Cart rule configuration — priorities, flags, exceptions.
4. 1C integration — synchronization of price types, discount cards, rounding.
5. Testing — load testing with 100+ active rules, conflict checks.
6. Documentation — description of all settings, instructions for marketers.
7. Manager training — how to create and disable promotions without risk.
8. 30-day support — fix any anomalies after launch.

Timelines

Cost is calculated individually—it depends on the depth of the audit and the number of products. Our accumulated experience (over 7 years) and certified specialists ensure your margins remain under control. Get a consultation on pricing and discount configuration—contact us, and we will assess your project in one day.