How much does it cost to ship a package? The short answer: it depends. The long answer: it depends on four very specific things, and one of them — the box you choose — is entirely within your control.
We have been selling shipping boxes to e-commerce and businesses in Spain and Portugal for over ten years, and this is the most frequently asked question. So let's answer it thoroughly: what exactly do you pay for when you ship, and how can you pay less without compromising the package's arrival condition.
What determines the price of a shipment
Four factors, in order of importance:
- Package size and weight. And beware, the scale doesn't always win: carriers charge for the greater of the actual weight and the volumetric weight. We'll see how now.
- Destination. Mainland Spain, Balearic Islands, Canary Islands (with customs), Portugal, rest of Europe… each zone has its own rate.
- Delivery time. 24h, 48-72h, or economy delivery. Urgency comes at a price.
- How you book it. The same shipment can cost differently at a counter, on the carrier's website, or through a comparison site. Booking online is usually cheaper.
In 2026, Correos parcel shipping also increased by 3% — the general trend in the sector is upwards, so optimizing your package is becoming increasingly worthwhile.
Volumetric weight, explained in one minute
This is where most people overpay without realizing it.
Carriers don't just weigh your package: they measure it. Because a van fills up with space faster than with kilos. The usual formula is:
Volumetric weight = length × width × height (in cm) ÷ divisor
Each carrier uses its own divisor, typically between 4,000 and 6,000. An example with a divisor of 5,000: a 40×30×20 cm box is 24,000 cm³ ÷ 5,000 = 4.8 kg volumetric weight. If your contents weigh 2 kg, you'll pay as if they were 4.8 kg. The box is costing you money.
That's why accurate measurement is so important — we have a quick guide on how to measure a cardboard box and a volume calculator so you don't have to do the math manually.
Approximate prices (and where to look them up)
Without committing to figures that change every January: a small national package usually ranges between €4 and €10 depending on service and delivery time, and then increases with weight and urgency. Correos' Paq Estándar accepts up to 30 kg; private couriers (SEUR, GLS, MRW, NACEX…) operate in similar ranges with faster deliveries.
Three practical tips:
- Always check the current rate on the carrier's website — they change every year.
- Shipping comparison sites group the volume of many customers and get prices that individuals don't see at the counter.
- Delivery to a collection point is usually cheaper than home delivery.
How to pay less: start with the box
It's the most overlooked and most profitable lever:
- Box adapted to the product. Every centimeter of air is volumetric weight you pay for and void filler you buy. With more than 40 sizes of single-wall shipping boxes, there's almost always one that fits your product.
- Move down a tier. Rates are structured by weight and size tiers. Sometimes, going from a 40×30×30 box to a 40×30×20 box can drop you an entire tier. Our box size guide helps with fine-tuning.
- Are you sure you need a box? For textiles or flat, non-fragile items, a padded envelope saves volume and money. We compare both in boxes vs. envelopes for online shipping — and here are the shipping envelopes.
- Lightweight void filler. Kraft paper or bubble wrap weigh little; adding useless weight "to prevent rattling" is expensive. More ideas in eco-friendly alternatives to bubble wrap.
If you ship often (e-commerce and B2B)
With more than 10-20 shipments per month, negotiate. All courier services have volume rates, and comparison sites serve as a benchmark to push for better deals. Standardizing 2-3 box sizes for your entire catalog simplifies negotiation, warehousing, and void filling — it's one of the first things we recommend to our B2B clients.
Frequently Asked Questions
What's cheaper, Correos or a private courier?
For non-urgent individual shipments, Correos is usually competitive. For frequent or 24-48h shipments, private couriers and comparison sites usually win. The best answer: compare your specific case, as it varies by zone and weight.
What is the volumetric weight of a package?
It is the theoretical weight resulting from multiplying length × width × height in cm and dividing by the carrier's divisor (usually between 4,000 and 6,000). If it exceeds the actual weight, that's what you're billed for.
How do I cheaply ship a large, light package?
Reduce volume: use the tightest possible box and, if the product allows, disassemble or fold it. For large, light packages, volumetric weight rules — every centimeter counts double.
Does the box really affect the shipping price?
Yes, twofold: it determines the volumetric weight and the size tier. A well-chosen box can save more than changing carriers.
The right box, delivered to your door
At TeleCajas, we have more than 200 packaging references with VAT included, 24-48h delivery in mainland Spain, the Balearic Islands, and Portugal, and free shipping from €30. If you tell us what you're shipping and where, we'll help you choose the size via WhatsApp: +34 665 53 23 58.
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