Travelling between Dublin and London can be fairly cheap and fairly easy. This is my guide to how to do it. I live in London and I'm from Dublin, and at the moment I travel between the two far more than any climate conscious person really ought to, but I'm definitely a frequent flyer when it comes to love miles. My commitments to family and friends in both locations are strong, and occasionally there is even some pesky work that has to be attended to in person in one jurisdiction or the other. Lately I've been back to Ireland from the UK around once a month, and I've done it at different times by plane, boat and train, in and out of every airport in London, to and from Dublin and several other airports around the island. I've learned many tips and tricks on these trips, which can make it cheaper and easier (and sometimes even both at the same time) to make the journey, so I'm sharing them here. I also want to subtly encourage more folks from there to come and visit me here in London - it's quite the city. I've written some version of this guide many times over for friends planning a trip to Londinium, so I'm finally putting it all together here for easy access. I've framed it in terms of travel from Dublin to London, rather than the other way around, but it should not be beyond you to apply it in reverse. Hope it shall prove useful, and please add comments below.
Ferry and train from Dublin to London
One good option to travel between Dublin and London is by ferry and train. This has the major advantages of being fairly cheap, about €90-100 return, even if booked the day before you travel, and always being the same price, so no need to worry about price changes. You can even show up at Dublin Port on the day and buy your ticket, which has a slight surcharge for same day travel, and you'll be in London later that day. There are two ferry companies, Irish Ferries and Stena Link, running the route from Dublin Port to Holyhead in Wales, and connecting to trains to London Euston station, in central London. They connect up with a variety of train companies as the rail system in the UK is fragmented, but this doesn't much matter, your ticket will take you on the relevant train by whichever company or companies are running it. The trains meet the ferries. There are fast ferries which take about 90 minutes and slow ferries which take about 3 hours. However because of the way the trains are scheduled the fastest you can do the whole journey is about 7 hours from Dublin Port to London Euston, and more usually about 8-9 hours depending which ferry or train you get. Obviously this is a long journey, and there can be delays on the ferry or train but there usually aren't. It has other advantages such as being able to show up at Dublin Port say 30 minutes before your ferry, and for the train in London 10 or 15 minutes before it is due to leave. When you factor in travel to and from the airports for flights, and the time in advance of your flight you need to be there, travel between Dublin and London by air can easily take around 5 hours door to door. Also the train brings you directly into Euston station which is central London, so you do not have to travel in from outside the city or from a distant airport after you arrive, and there are no additional travel costs. There is essentially unlimited luggage allowed on the ferry, you can check usually two bags while carrying another one with you onto the ship, for free. The ferry-boat combo is called SailRail from Dublin to London, and sometimes called RailSail in the other direction. Travelling by boat and train is also more ecologically friendly than travelling by air, with far lower carbon emissions, depending on the capacity and occupancy of the ferry, mainly. I have travelled many times on the boat and train to and from London to Dublin and found it quite relaxing, entertaining, and good value, despite the fairly long hours. Worth considering, especially if it's close to your travel date and prices are climbing.
Flying from Dublin to London
Four airlines currently fly between Dublin and London: British Airways (BA), Aer Lingus, Cityjet and Ryanair. There are five major airports in London, all with flights from Dublin: London City (airport code is LCY), Heathrow Airport (LHR), Gatwick Airport (LGW), Stansted (STN) and Luton (LTN).
Tips and tricks:
Not all airlines fly to all airports. You will need to search on each airline's website for their flight routes. It is worth checking the individual routes for each airport with the airlines, as prices to one London airport can vary radically compared to another airport, even on the same day and almost the same time of flight. At the moment (August 2016) BA flies between Dublin and Heathrow, Gatwick and London City. Aer Lingus flies between Dublin and Heathrow, Gatwick and London City. Cityjet flies only to London City. Ryanair flies to Stansted, Gatwick and Luton.
Definitely consider buying one way with one airline and return with another airline, if it is cheaper. All airlines sell one way flights on these routes, usually at little or no difference in price compared to one leg of a return. And one airline and airport in one direction may be radically cheaper while its return is much more expensive, and vice versa. You can also fly with the same airline into one London airport and out of another. It may be cheaper and may suit you better or make no difference to you to travel in to one place and out of another. So consider buying two singles with two different airlines and/or two different airports, and you can potentially save a lot.
Return flights are sometimes cheaper than two single flights made with the same airline. But for some airlines the prices are identical. Other airlines, buying a one way flight is €5 or €10 more expensive than the price listed for that leg as part of a return. But sometimes, with the same airline, buying a single is much cheaper than the leg as part of a return. I do not know why this is (any ideas, airline employees?), but I've had it happen enough times to know it is worth checking one ways as well as returns. It may be because when you buy a return, if one leg of it only has seats available at a higher price, then both flights get bumped up to the higher price bracket, costing you more overall. There is not necessarily any advantage in buying a return. Again, it is definitely worth checking two one way flights.
On some of the websites, you can enter London (code LON) or something like London England Area instead of an individual airport and it will bring up all flights by that airline to all the airports in London, saving you having to check each route individually. This is because London has its own “all airports” code for the whole city, like other hubs with multiple airports such as New York (NYC), Berlin (BER) and Paris (PAR). Annoyingly this is not possible on every website, and strangely, does not work reliably on some – for example, entering LON on the Aer Lingus website will bring up flights to Heathrow and Gatwick but not London City, for which you have to search separately.
Most of these airlines and routes are either not listed or not listed correctly on aggregator websites, like Skyscanner or Kayak, though these can give an indication of who flies where. Occasionally a cheaper flight may come up on one of these websites but I have never found it to be the case. It is a bit time consuming and annoying having to check the four airline websites and their routes into the five London airports, and of course each website loves to do things in its own idiosyncratic and highly irritating way, but with a bit of patience and multiple tabs in your browser, you can sometimes save some serious cash.
Every so often another airline starts flying between Dublin and London. Up until recently, FlyBe flew this route, which was great because its propellor planes are much more environmentally sound, it was cheap, they have lovely staff and service, and they also flew to unusual regional airports around the UK – handy if you were going outside London. Occasionally an airline flies the route only at a certain time of year, or flies more often during certain seasons. I have the feeling that Easyjet and Aer Arann once flew this route, but I could well have imagined that.
Some of these four and other airlines also fly from London to Knock and Shannon airports in Ireland and to Belfast's two airports in Northern Ireland. I've flown some of these routes and sometimes they are cheap and fast, but there are usually one or maximum two flights a day. There are also flights from Kerry and Cork direct to London though I haven't taken any. Depending where you are coming from, flying out of a regional airport can work out well.
The flights themselves take about an hour to an hour and twenty minutes. There isn't much difference between flight times from Dublin to individual London airports. Your plane will probably only be in the air for between 45 and 60 minutes. Not lots of time to work or relax between the seatbelt signs going on, when you'll have to put your laptop away. Bear in mind that if your flight is delayed, early, or cancelled, being at a major airport (like Heathrow) can be an advantage in terms of getting another flight out, but a disadvantage in terms of missing your scheduled landing time and having to circle for ages.
Don't be misled by airlines that seem to fly this route but in reality are merely codeshares with one of the four airlines above, i.e. one airline runs the flight but another airline can share the code to also claim it as one of its flights. Air France is sometimes listed but is just a codeshare with Cityjet. Aer Lingus flights to London City are in reality BA flights in codeshare. Almost always buying the flight with the codeshare partner is more expensive than buying it directly from the airline that is actually flying the plane.
There are many other airlines that fly indirectly between the cities. If desperate, you could probably take a flight that stops somewhere else in the UK first, but that would definitely be time-consuming and probably be expensive. Alternatively if you want to pay hundreds of euro, spend five or more hours flying for a supposedly hour long flight, and 'stop off ' in Copenhagen or Paris airports 'en route' between London and Dublin, go ahead. Personally, I'd say that's unwise.
Obviously flights tend to go up in price the closer you get to your planned departure date, but very occasionally the reverse is true and a few flights at a cheaper price are released closer to the date. I have also noticed that sometimes Ryanair in particular reduce the price of their flights by a few euro during the night – literally the price will go down at say 10pm at night, if you buy it then, but then in the morning it goes back up to what it was before. Bizarre but I have made use of this. However in general I would say buy as soon as you can, as prices usually just keep climbing closer to the time you're flying.
For the best views, I recommend sitting on the right of the plane when flying into London. Especially into London City, which really is in the middle of the city, and where you sometimes fly basically along the Thames over the London Eye, Big Ben and the Houses of Parliament, before landing on the runway which is built out into the water and makes you feel like you are about to clip the buildings on either side as you come in for your approach. On a clear day even a jaded jetsetter will find it hard to stop themselves glancing out the window.
My views on the airlines:
BA is generally an extremely pleasant airline to fly with and can be very good value, cheaper than some others. They have tonnes of flights per day between Dublin and London. It is usually relaxing, efficient and stressfree, and you even get free food. It is like flying used to be. I have realised part of the reason it is relaxing flying with BA is because the cabin staff are there to save your life and serve you coffee, not to try and sell you stuff like on the budget airlines. Essentially nothing is for sale on a BA flight so the staff are not stressing trying to flog you an overpriced panini and scratchcards. They are based out of Heathrow which has advantages. Also they have astonishing baggage allowances – see below. Aer Lingus is alright, usually pleasant enough and on time, and sometimes cheap, with lots of flights per day between the cities. No free food and lately a good bit of upselling to put up with as it competes to the bottom. Cityjet is quite remarkable as an airline in terms of price and service. They fly only via London City which is very handy – see below. Cityjet used to market themselves as a business class only airline. Despite this I have gotten extremely cheap flights with them at times. It seems to follow no pattern, as sometimes their flights are astronomically expensive (but then so are everyone else's) but don't be put off by their pretensions, it is worth checking them out, even if, like me, you are clearly not anything like the businesspeople they try to woo. Also pay by Paypal or they will slap on a hefty payment charge on credit cards, about €5. I have no idea why either. Ryanair can be fairly cheap, relatively on time, and have lots of flights from Dublin to their three London airports. It is important to factor in the cost of getting to and from these airports into the overall cost of your travel – see below. Even without this, despite the automatic assumption that Ryanair=cheap, I have found other airlines often beat them on price. You will need to be prepared to tolerate them not having enough space on the plane for everyone's (packed to within a gram of the limit) hand luggage, and being forced to check yours (for free) and thus wait for it on the other end. There is also their constant selling of everything including bus tickets and three cheese pizza (because they are too cheap to do the usual four cheese pizza – no 'quattro formaggio' here). But at least they now allocate seats rather than the mad free for all endless queue and melee 'system' of yore.
Bottom line is that all four airlines are fine, are safe, can all be cheap, and will most likely get you from Dublin to London without any hitches or delays, and with varying degrees of pleasantness and sustenance during the flight, which all take about the same duration.
Two other key factors in choosing your airlines and route are the issue of getting to and from the airports in London, and baggage allowances. So important are these that I've given them their own sub-sections. Because sub-sections are cool.
Getting to and from the airports in London:
London is a large and spread out city of about 9 million people and its five airports are in very different locations, mainly way outside the city proper. It isn't that large by mega-city standards, it's not that sprawling and its transport systems are very good, but getting to and from the airport is a major factor in terms of both cost and time in your overall journey. The city is divided into nine zones (really six of importance) for public transport, which go in rings from Zone 1 in the centre of London outwards to Zone 6 and ultimately Zone 9. Zone 1 and 2 are very central and it's rare to go beyond Zone 3. Public transport is made up of the Underground, commonly known as the Tube, and its integrated other forms including the Overground, DLR (Docklands Light Railway) and commuter rail. The public transport system uses Oyster cards which can be purchased for £5 at any Tube station – definitely do this as tickets are about half price with such cards, it is otherwise difficult to buy tickets for each journey, and you can give the Oyster card back and have the £5 refunded at most stations when you leave London. Alternatively you can use cash. There are also London Buses which are public transport and only take Oyster cards – as of at least 2015 they do not take cash. There are also private coaches, private/express trains and taxis (the famous London Black Cabs, as well as private hire and account services such as Addison Lee). London City and Heathrow airports are within the zones and accessible by public transport, making them cheap and quite fast to reach, while the other three airports are all outside the city, meaning it requires time and private trains, buses or taxis to reach them.
London City is the only airport that is really in London itself. It advertises itself as such, and it's not lying. It is pretty much in the central docklands of east London. It is in Zone 2 i.e. very close to the centre and there is a DLR stop at the airport. It is possible to get off the DLR train and be at your gate, including having cleared security, less than 10 minutes later – I have done this more than once. It's a small airport with the pluses that brings – easy to get to and around, fast, accessible – and the minuses – not that many flights, bit run down. London City also advertises itself as having the easiest check in/boarding time cut off of any airport – you can be at the gate 15 minutes before your flight. It's quite reasonable to reach the airport say 30-45 minutes before your flight if you've no luggage. The best/worst I've ever done was that I once got off the DLR at London City at 14.22 for a 14.25 regional flight to Scotland and still made the flight, though I had to bang on the locked boarding gate to convince them to let me on – I don't recommend cutting it quite this fine. The airport is convenient for anywhere in or outside London, particularly to the north or east. Because it's in Zone 2 and has a public transport station actually at the airport it is very cheap to get to and from it by Tube/DLR - a journey to Zone 1, 2 or 3 is about £2.50. It is also fast – there are trains every few minutes and it takes maybe 20-30 minutes to reach most places in central London by DLR/Tube from London City.
Heathrow is in Zone 6, a bit far off to the west, and also has a Tube station at it. This makes it very handy. It is a massive airport and takes quite a long time to navigate through or to move between terminals, ensure you leave plenty of time to get to and from it and to clear security. It is on the Piccadilly line on the Tube, and there are three stops for it, depending on your terminal – Terminals 1, 2 & 3, Terminal 4 and Terminal 5. It takes about 50-60 minutes to get to most places in central London on the Tube from Heathrow, direct on the Piccadilly line, with trains running every few minutes. This costs about £5 using your Oyster card. Alternatively you can get the Heathrow Express private train, which is fast – it takes about 15-17 minutes to Paddington Station and runs every 15 minutes – but expensive – about £20. There is also the less well-known Heathrow Connect private train which takes about 30 minutes and runs about every 30 minutes, and is, guess what, £10. I imagine there are buses from Heathrow too which may be cheap but hard to imagine they are cheaper or faster than the Tube, have never tried them. If you ordered a taxi or Addison Lee car between a few people it could work out ok. Heathrow is convenient for anywhere in or outside London due to its transport connections. If you are headed outside London to Reading or Windsor in the west it would make most sense.
Stansted Airport is far outside London to the northeast. You have to get a private train or coach there, there's no Underground. The Stansted Express train takes 36 minutes to Tottenham Hale Tube station or 47 minutes into central London to Liverpool Street Station (these are usually the only two stops). Tickets are usually £19 one way, but can be £8 if you get an advance, or about £16 for a WebDuo or group slightly reduced price for two or more people travelling together. Quite often the trains are replaced by buses, especially at weekends, so check their website for scheduled Service Alterations before you buy. There are a variety of private bus companies between Stansted and London, such as National Express. Buses cost from £5 to £12 to get into central London, depending where you are going, and take 60-100 minutes. It is not unusual to be on the bus for 90 minutes or to get further delayed. The coaches stop in a few places such as Stratford en route to Victoria or Paddington stations. I have taken these buses a few times. Have never taken a taxi but it is conceivably possible, potentially very expensive as it is a long distance. Stansted is particularly handy if you are going to the north east of London such as Hackney or Finsbury Park, because Tottenham Hale station where the trains and sometimes buses stop is in that vicinity.
Gatwick airport is outside London in the south. So it is handier if you are going to south London. You have to get a train or coach there, there's no Underground. You can take the Gatwick Express train which takes 30 minutes non-stop to Victoria station and runs every 15 minutes. It costs £20, sorry, £19.90. Slightly less if you get your ticket online or with two people travelling together. There are also standard commuter trains run by Thameslink which take about 50 minutes into central London stations and cost about £10. The Thameslink trains are not advertised so visibly as the Gatwick Express but they run about every 20 minutes and go to a variety of stations. There are also coaches, which I haven't yet tried.
Luton airport is way outside London in the north west. You have to get a train or coach there, there's no Underground, and it does not have an 'Express' service, making it a bit trickier to get to. You can get a Thameslink train to Luton Airport which actually stops at Luton Parkway and a shuttle bus takes you to the airport itself. Trains run to various stations in central London every about 15 or 20 minutes, take about 50-60 minutes including the shuttle (though this depends on traffic) and cost about £15 one way. If you don't specify Luton Airport on your train ticket, rather than Luton Parkway which costs the same, you will be charged another £3 for the shuttle bus. There is often traffic which can delay the shuttle bus quite a lot. While ostensibly as close as say Stansted, Luton just takes more time to get to, quite a long time to get through as an airport and is more prone to delays. There are also coach services direct to Luton airport, such as Easybus and National Express, which in theory take around 50 minutes to central London, but I have never tried them.
The four airlines have quite different hand luggage and checked baggage allowances and costs. So if you are looking to take more than a few kg with you, factor this in. BA allows you to take 23kg for free as hand luggage. Yes, you heard correctly, twenty three kilograms. That is on either a hand-luggage-only fare or a fare with hand luggage and a checked bag. The checked bag allowance is also 23kg, which is included in any fare with a checked bag. So you could take 23kg hand luggage and a 23kg checked bag, no problem. I think you can also take a 'small' personal bag in hand luggage on BA, such as a handbag, manbag, laptop bag, or small shopping bag, in addition to the 23kg, but haven't checked this recently. Cityjet also give you a generous 12kg hand luggage allowance and 23kg free checked bag on all their flights, even the cheapest fares. They will not look twice at you also bringing a personal bag. Ryanair and Aer Lingus on the other hand have the standard 10kg allowance for hand luggage. On Ryanair nowadays you can also take a small personal bag in addition, and usually also on Aer Lingus but they didn't used to specify that, they may have updated their terms recently. Be warned that Aer Lingus flights to London from other airports than Dublin can be termed 'regional' flights and thus the hand luggage allowance is only 7kg. On Ryanair or Aer Lingus you must pay extra to check a bag, which can be anything from €15 to €30 per bag. If you don't need much stuff with you, none of this will matter, but if like me, you have emigrated and de-emigrated multiple times, or are splitting your life between two cities, then it pays to think all this through.
No doubt there is more to say on all of this, and updates and corrections to be made constantly, but hopefully it's pretty much correct as of this moment, and that's enough to be getting on with. Happy travels!