Ancillary services are a staple in the travel industry. Any agency, airline, or even a travel tech brand wants to boost revenue streams and push profitability. And although it’s easy to find what ancillary services in tourism are, nobody’s trying to explain what businesses are actually interested in: how do they affect profitability, and how do you choose the right ones to offer? 

As a travel eSIM platform, esimba.ai has helped many brands boost their revenue through eSIM reselling, a primary ancillary revenue source today. With years of partnership experience, we’re ready to make the case for such add-on services. Let’s discuss what they are, how businesses implement them, and how to measure whether a given service is pulling its weight. 

What Are Ancillary Services in Tourism?

Ancillary services in tourism are optional products and services sold alongside a core travel booking, such as a flight, a hotel stay, or a package. Common examples include travel insurance, car hire, airport transfers, tours, baggage and seat upgrades, and eSIM data plans. The traveler pays for them separately, and the business that sells them earns revenue on top of the original booking. 

Ancillary services have grown well beyond the handful of examples most people associate with them. They span categories and no longer just mean insurance and car rental. 

Examples of Ancillary Services 

Here’s how the most common ancillary services break down: what they are, who usually sells them, and how the seller earns from them.

The mobile travel booking market will reach $612.5 billion by 2031, with a predicted CAGR of 10.7%. A lot of this growth directly ties to ancillary services and how commonly associated they are with any travel brand, and, by extension, their revenue stream.  

Why Ancillary Services Matter for Profitability

Profitability increases because ancillary services target your core audience, and customer acquisition is not a factor; that’s the first actual benefit. But there are many more:

• Higher margins than the core product. Because you're not paying to acquire a new customer, ancillary services tend to carry better margins than the seat, room, or package they're attached to.
• A natural fit with low-cost strategies. This is part of why low-cost carriers leaned into ancillary revenue so heavily in the first place. Unbundling the fare from the extras let them compete on headline price while making up ground on everything sold alongside it.
• Stronger loyalty and differentiation. A well-timed offer, an airport transfer arranged in advance, a data plan ready before landing, adds convenience at exactly the moment a traveler needs it. That tends to translate into repeat business and better word of mouth.
• Data that improves everything else. Every ancillary purchase tells you something about traveler preferences and spending habits. That data can sharpen future offers, personalize marketing, and make the next sale easier than the last.

Customizability as a Profitability Lever

Another major argument for ancillary services is customizability. A lot of the time, the company worries that adding additional products will dilute their offer and skew perception. And although you can’t necessarily provide insurance through your own brand, you can find fully white-label integration options for certain ancillary services, like with eSIMs. 

For instance, at esimba.ai, we can produce a fully customized webstore, a white-label app or miniapp, and even allow you to customize bundle design and data amount. As a result, you can better sell the new product and target niches within your general audience without changing the brand name. 

Measuring Profitability: What to Track

Deciding to offer a service is the easy part. Knowing whether the ancillary spend justifies ROI is where businesses fall short, mainly because they're not tracking the right things from the start. A few metrics make the difference between guessing and knowing:

• Attach rate. The percentage of travelers who purchase the ancillary service out of everyone who could have. This is the clearest signal of whether the offer, timing, and price are actually landing with your audience. A low attach rate usually points to a problem with visibility or relevance, not demand itself.
• Revenue per traveler or ARPU. Rather than looking at total ancillary revenue alone, break it down per traveler or per booking. This makes it far easier to compare performance.
• Margin per category. Not all ancillary services are equally profitable. Some carry near-zero marginal cost once the infrastructure is in place; connectivity is a good example, while others involve ongoing operational costs like staffing or third-party fees. 
• Repeat purchase and retention impact. Ancillary services often influence loyalty long before they show up as a line item. Tracking whether travelers who buy ancillary services return more often, or spend more on future trips, helps justify the investment.

A Simple Framework Before Committing

Before adding a new ancillary service, it helps to ask three questions:

1. Does it fit naturally into the existing journey? Services that require extra effort to notice or book tend to underperform regardless of how useful they are.
2. Can it be implemented without major operational strain? The best ancillary services, connectivity included, often run through a partner's infrastructure rather than requiring new internal systems.
3. Is there a clear path to measuring it? If attach rate, ancillary spend, and margin can't be tracked from day one, profitability becomes a guess rather than a number.

Services that clear all three tend to be the ones worth prioritizing, and the ones most likely to hold up once the novelty wears off.

The Downsides: What to Weigh Before Adding Ancillaries

Ancillaries aren’t free money. A few trade-offs are worth planning for before you launch:

• Fee fatigue. Unbundling has a cost in goodwill. As travel tech provider TTS puts it, “Nobody likes to feel like they’re being nickel-and-dimed by their airline,” and some travelers now want bundled options back. Price add-ons clearly, offer them when they’re relevant, and consider bundles for travelers who prefer one price.
• Your brand carries the partner’s mistakes. When a transfer doesn’t show up or a data plan doesn’t connect, travelers blame the brand they bought from, not the supplier behind it. Vet partners on coverage, support response, and how they handle refunds.
• Attach rate has a ceiling. Not every traveler needs every add-on, so revenue grows with booking volume, not just with how many products you list.
• Support load. Your team will field questions about products it doesn’t run. Partners that handle customer support directly, or train your agents, reduce that load.
• For connectivity specifically: network coverage varies by region, and some older phones don’t support eSIM. Check compatibility at the point of sale to avoid refunds.

None of this rules out ancillaries. It’s why the three questions above matter: services that fit the journey, run on a partner’s infrastructure, and can be measured from day one tend to hold up best.

How B2B Partners Actually Implement Ancillary Services

Once a business decides an ancillary service is worth offering, the next question is how to actually add it without disrupting existing operations. In practice, most implementations fall into one of three models, and the right choice often depends on the type of service itself. 

API Integration

This is the most flexible option for businesses that want the ancillary service embedded directly into their existing app or booking flow. It takes more development work upfront, but gives the business full control over how the service looks and behaves.

For eSIM and connectivity, a travel agency or fintech app connects to a provider's API so travelers can activate a data plan without ever leaving the platform (learn more here). Travel insurance follows a similar pattern, with larger OTAs integrating providers via API so a policy can be quoted and added at checkout in real time. Wi-Fi and communication services work the same way, with airlines and hotel groups connecting directly to connectivity providers so access can be offered and billed as part of the existing booking flow.

White-Label Solutions

For businesses that want to offer a service under their own brand without building the underlying infrastructure, white-label is often the faster route. The provider handles the technical and operational backbone, while the business handles the branding and customer relationship.

Car rental is a common example, with many travel agencies offering rental cars "as their own" while the partner manages fleet logistics and local operations behind the scenes. Lounge access works similarly, with airlines and card issuers offering programs branded as their own, powered by a third-party network operating the actual locations. Medical and wellness services follow the same pattern, with hotels and resorts presenting spa offerings under their own brand while a specialized operator runs the treatments and staffing.

Reseller and Referral Partnerships

The lightest-touch option, where a business simply promotes or resells a partner's service and earns a share of the revenue, with no integration work required.

Event and entertainment tickets are a natural fit here, with concierge services and hotels referring guests to local ticketing partners and collecting a referral fee rather than managing inventory. Guided tours work the same way, with smaller agencies and hotel front desks recommending a local tour operator and earning a commission per booking. eSIM providers also create affiliate programs which net you 5%-10% as commission per bundle sold.

Margins and Profitability for Ancillary Services in Tourism

As to the actual margin examples, things can get extremely complicated when we consider all ancillary services. Most companies don’t publish their sales data, nor report on how profitable certain endeavors were. However, what we can do is talk about margins and profitability for our clients. 

One of the more representative examples is our current partner, Nikana. We’ve already talked about them in this blog, and their results were impressive. In just 5 months after launching their webstore with us, they were able to make $68,200, with a net profit of $30,328 and a net margin of 44.5%. Initially paying $1,000 for webstore development, they made 30x the investment and managed to achieve an average revenue per user (ARPU) of $18.15. 

esimba.ai and Why It’s the Right Connectivity Partner

Although we can’t make recommendations for every ancillary service in tourism, we can confidently attest to how profitable eSIMs are. At esimba.ai, we’ve been partnering with travel agencies, airlines, and even MICE companies for years. We have a vast portfolio and a proven track record of success. 

By gaining access to our platform, you can enjoy analytics, line management, automations, a deep level of customization, and more. Our main brand, Keepgo, is fully established on the market, with each bundle being carefully curated and developed for a particular client niche, making it much easier to resell after establishing a partnership. 

We have a single reseller program with two partnership types: self-serve and turnkey. The first costs next-to-nothing to setup, and all that’s required from you is to follow this link, register and top up the balance for $50 to unlock wholesale rates. Our rates for solutions are custom, with competitive pricing and timely delivery.