The Real Cost of a ‘Cheap’ Ryanair Flight from London to Dublin: Baggage and Seat Fees.

💰 Prices updated: 2026-04-01. Budget figures are estimates — always verify before travel.

The £9.99 Lie (And Why It’s Not Really a Lie)

Ryanair’s London to Dublin route is one of the busiest short-haul corridors in Europe, and for years it has been dangled in front of travelers with headline fares that seem almost offensively cheap. A tenner to cross the Irish Sea? Surely not. The truth is more complicated — and more expensive — than that splash-screen price suggests. Ryanair doesn’t hide its fees exactly; it buries them in a booking flow designed to extract maximum revenue at every click. By the time most travelers reach the payment confirmation screen, that £9.99 base fare has quietly ballooned into something between £40 and £120 per person, depending on how much luggage they carry and how much attention they paid during checkout. This guide unpacks every layer of that cost, so you know exactly what you’re agreeing to before you hand over your card details.

How Ryanair’s Pricing Structure Actually Works

Ryanair operates on an ultra-low-cost carrier (ULCC) model, which means the base ticket price is intentionally stripped of almost everything. Unlike a traditional airline where a fare includes a checked bag, a seat assignment, and maybe a snack, a Ryanair fare in its purest form includes only one thing: a small personal bag (roughly 40cm x 20cm x 25cm) that fits under the seat in front of you. Everything else costs extra.

The base fare itself fluctuates wildly based on demand, booking window, and time of travel. London to Dublin can genuinely be booked for under £15 in certain windows — typically six to twelve weeks out, on Tuesday or Wednesday departures, avoiding school holidays and bank weekends. But that price is a ceiling that exists for a limited number of seats on each flight. Most travelers booking within four weeks of departure, or flying on a Friday or Sunday, will find base fares sitting between £30 and £60 before a single extra is added.

Ryanair generates a significant portion of its revenue — reportedly over 30% — from what it calls “ancillary” income. That is industry jargon for fees. Understanding this is not a cynical exercise; it is genuinely useful knowledge that lets you game the system rather than be gamed by it.

Baggage Fees: Where Most of the Money Goes

This is the category that catches the most travelers off guard, and it is worth understanding in granular detail because the fee tiers are genuinely confusing by design.

The Free Personal Bag

Every Ryanair passenger, regardless of fare type, is entitled to one small personal bag with maximum dimensions of 40cm x 20cm x 25cm. This is smaller than most airline carry-ons and smaller than a standard backpack. It must fit entirely under the seat — not in the overhead locker. If you can travel with only this, your baggage cost is zero. Most people cannot.

The Cabin Bag (10kg, Overhead Locker)

To bring a normal carry-on bag into the overhead locker, you need either to purchase Priority Boarding or to pay a standalone cabin bag fee. As of 2026, Priority Boarding on the London–Dublin route costs between £6 and £14 each way depending on when you book, and it includes the right to bring a 10kg cabin bag into the overhead locker along with your personal item. If you try to bring an oversized personal bag without Priority Boarding, ground staff will charge you at the gate — a punishing £/€50 per bag. This gate charge is intentionally steep; it exists as a deterrent and a revenue mechanism simultaneously.

Checked Baggage (20kg Hold Bag)

Adding a 20kg checked bag to a London–Dublin booking typically costs between £14 and £28 per bag per flight when added at time of booking. The same bag added after booking but before online check-in closes costs noticeably more — around £20 to £35. Added at the airport desk, it will cost £50 or more. For a return trip with one checked bag added at booking, budget approximately £28 to £56 on top of your base fare, before anything else.

If you’re travelling as a couple with one shared checked bag, you’re looking at roughly £14–£28 each way. For a family of four each needing a bag, that checked luggage line item alone can exceed the combined base fares.

Seat Selection Fees: Paying to Sit Somewhere Specific

Ryanair assigns seats automatically at no charge — but only at check-in, which opens 48 hours before departure. If you do not select a seat yourself, you will be assigned whatever remains, which is usually a middle seat toward the back. For a one-hour flight, most people can survive this. But there are reasons you might want to pay for a specific seat.

Standard seats (rows 3–33, window and aisle) cost between £4 and £9 per seat per flight on the London–Dublin route. Front seats (rows 1–5, additional legroom) run between £12 and £24 per seat per flight. Exit row seats with significantly more legroom cost between £12 and £24 as well. On a return trip, a couple choosing standard seats at the cheaper end could add £16–£36 to their bill. Two travelers paying for extra legroom seats on both legs might add £48–£96.

Critically: if you book Priority Boarding, Ryanair does not guarantee you a specific seat — it just guarantees you board earlier and can use the overhead locker. Seat selection and Priority Boarding are separate charges.

The Other Charges Ryanair Adds Along the Way

Payment Fees

Ryanair charges a fee of approximately £2 per passenger per flight when paying by credit card through certain channels. Using a Visa debit card or prepaid card usually avoids this. On a return trip for two people, this can add £8 to your total for no tangible service.

Check-In Fees

Online check-in is free if done between 48 hours and 2 hours before departure. If you miss that window and need airport check-in, the fee is £55 per person. This is one of Ryanair’s most notorious charges and it catches travelers who forget, or who are traveling internationally and have passport-related complications. Set a calendar reminder for 48 hours before your flight. Do not skip this.

Travel Insurance

During booking, Ryanair pre-selects a travel insurance option. You must actively deselect it or you will be charged. The insurance itself costs around £7–£12 per person for a short trip. Whether or not you want it, be aware it is selected by default.

Fast Track Security

At Stansted, Gatwick, and Dublin, Ryanair sells fast track security access for approximately £5–£9 per person. This is optional and genuinely useful during peak morning slots. It is one of the few add-ons that delivers fairly transparent value.

Airport Transfer Costs (London Side)

Ryanair flies London–Dublin from Stansted, not Heathrow or Gatwick (though some services do operate from Gatwick). A return National Express coach from central London to Stansted costs roughly £20–£30. The Stansted Express train runs £35–£50 return. If you booked a cheap fare from Gatwick instead, factor in the Gatwick Express or Southern Rail cost. These are not Ryanair fees, but they are a direct consequence of budget airline routing and need to appear in your real-cost calculation.

Money-Saving Strategies That Actually Work

• Book directly on Ryanair.com. Third-party booking sites sometimes add their own service fees on top of Ryanair’s fees. The airline’s own site is almost always cheaper.
• Add bags at booking, not after. Baggage prices increase after the initial booking is confirmed. Add everything you need on the first checkout screen.
• Travel with a personal bag only. Invest in a well-designed 40L backpack that compresses to fit Ryanair’s under-seat dimensions. Osprey, Tortuga, and Cabin Zero all make options built for this exact constraint.
• Fly mid-week. Tuesday and Wednesday departures are consistently cheaper on this route. Friday evenings and Sunday afternoons are the most expensive slots by a significant margin.
• Use a Visa debit card. Avoid the credit card payment surcharge entirely.
• Set a check-in alarm for 48 hours before departure. Missing the online check-in window is the single most expensive mistake a Ryanair passenger can make.
• Skip seat selection if you’re a solo traveler. You’ll be assigned a seat regardless. The risk is a middle seat, which on a 55-minute flight is survivable.
• Compare total costs with Aer Lingus. On this specific route, Aer Lingus regularly runs sales where an inclusive fare — including a carry-on bag and a seat — costs only marginally more than a fully loaded Ryanair booking. Always compare the full-cost equivalent before assuming Ryanair is cheaper.

Sample Journey Budgets for Three Types of Travelers

Shoestring: The Committed Budget Traveler

Books eight weeks in advance on a Wednesday morning, carries only a personal bag under the seat, uses a debit card, checks in online exactly 48 hours before departure, and skips all optional extras.

• Base fare (return): £28
• Baggage: £0 (personal bag only)
• Seat selection: £0 (random allocation at check-in)
• Payment fee: £0 (debit card)
• Stansted Express (return): £36
• Total: approximately £64 / $82 USD return

This is genuinely achievable but represents the floor, not the typical outcome.

Mid-Range: The Normal Leisure Traveler

Books three weeks out for a Friday–Monday trip, brings a 20kg checked bag, selects a standard aisle seat, pays by credit card, checks in online.

• Base fare (return): £80
• 20kg checked bag (return): £40
• Seat selection, standard aisle (return): £14
• Payment fee: £4
• National Express coach to Stansted (return): £22
• Total: approximately £160 / $204 USD return

This is the realistic median for a single traveler taking a weekend break.

Comfortable: The Traveler Who Wants Convenience

Books two weeks out, needs a 20kg bag, wants an extra-legroom front seat, adds fast-track security at Stansted, uses the Stansted Express.

• Base fare (return): £100
• 20kg checked bag (return): £56
• Front seat, extra legroom (return): £44
• Fast track security (return): £16
• Stansted Express (return): £48
• Total: approximately £264 / $337 USD return

At this price point, the comfort gap between Ryanair and Aer Lingus narrows considerably, and it is worth running a side-by-side comparison before committing.

The broader lesson here is not that Ryanair is a bad airline or that its pricing is fraudulent — it is simply that the advertised price and the real price are two different numbers, and knowing the gap between them in advance is the only thing that separates a savvy traveler from an annoyed one standing at a gate being charged £50 for a bag.

📷 Featured image by Maciej Karoń on Unsplash.