ATM alternative

...backup plan should we need more cash and run into issues...assuming if they accepted credit cards to hold our reservation, that we can also use that as our method of payment rather than cash...

It's a pretty good assumption that credit cards will be accepted to pay for your hotels. Small B & B facilities may be different. To be sure, try sending an email to cofirm your assumptions.

For a back up plan, try to have more than one debit / ATM card with you. Having them issued by different banks will add another layer of protection against the techno-gremlins that pop up from time to time. You might also consider getting one or two hundred Euros from your local bank, or even AAA. That will cost just a little bit more than getting them upon arrival, but it's a small price to pay to have some peace of mind if the gremlins do appear.

I wouldn’t count on being able to get cash back when charging something. You can always buy some Euros before going over, but chances are you won’t need many while there. Once you have an itinerary, look up ATMs for the cities and towns you’ll be visiting and you can bookmark them to Google maps. If whoever you have your debit/ATM card through has a partner bank in Ireland, check those locations. You could save some transaction fees.

Most attractions will accept credit cards and many parking machines accept cards too.

Forgot to mention, but be sure to check with your credit card, and debit / ATM people to see if a travel alert needs to be placed on your cards. Some do and some don't. You definitely do not want them to see a foreign transaction, think it's fraud, and lock down the account.

During the week we spent in Ireland last summer we used cash exactly one time. Ireland is a very high-tech place, and cash is almost never needed. I paid for a Dublin bus ride using exact euro coins.

Thank you so much for the tips. My bank is one that doesn't accept travel alerts any longer but said a phone call to them should straighten out any issues should my card be declined.

I will get a few euros to take over just for my peace of mind, but I expect that we will be spending it on snacks in the airport when we get ready to leave.

Get yourself some Euros before going over and chances are you won't need an ATM while there. You'll be surprised where you can use credit card/electronic payments.

To make life even easier, make sure your credit cards are contactless. You just tap and pay.

Or, if you use a smartphone, you could set up either Apple Pay or Google Pay--depending on which type of phone you have--and just use that as payment.

Most cash-only B&Bs will tell you on the reservation acknowledgement that they require cash. We almost always stay in B&Bs, so we run into them quite regularly. I just have a debit card that I use only for ATM machines while traveling, and except for being out-of-order, every bank has one outside on the sidewalk, and most towns have a bank.

For making all other payments (bus, restaurant, trinkets, lodging) I use "tap to pay" on my smartphone. In my case, I use Google Pay. Never need my physical cards. I use an EU Sim card while in Europe, so getting two level authorization via text or phone just won't work. All my cards support online travel scheduling, even my wife's small credit union.

If you have only one ATM/Debit account, then make sure you have a PIN for one or more of your credit cards, so you can get a cash advance from an ATM on your credit card. Not the best way to get cash for most people, but not bad for anyone if you have few other options.

In Canada, you used to ge able to ask for cash back at a grocery store.
Also, take some US cash to exchange in a Foreign exchange office...or bank. Always good to have some home cash on hand. Two or three hundred dollar bills in your money belt will go a long way to affording some peace of mind.

In the UK, on the other side of the Irish Sea, cash back is widely available in Grocery Stores.
I wouldn't expect that to be different in the Irish republic.

There's an elephant in the room here - actually, a couple of them - which have gone largely un-noticed, and the OP would be better served if responses were more clear about them.

First there's there's the OP's question (bolding is mine):

Is it an option to ask for cash back at a restaurant or pub, by asking
the waiter to add on certain dollar amount above the bill when using
a credit card?

The answer to this question is (I think) a clear NO. I've never seen an option (anywhere) to get additional cash back when making a purchase with a CREDIT card. With a DEBIT card, yes, but not with a credit card. And that's the whole point of the OP's thread: if their debit card fails or is unavailable. If they hope to get cash when buying groceries (a common option here in the USA at least) or someplace else, that only works with debit cards, not credit cards (someone please correct me if they've ever seen this option, anywhere, when using a credit card...I could be wrong but I simply don't think this is an actual thing). So that's one elephant - there's no option for cash back when purchasing something with a credit card, fuggedaboudit. You might be able to sweet-talk someone who's very kind to help you do this in a real crisis, but I wouldn't count on it.

The second elephant: A single point of failure. I think the OP's concern boils down to that, and that is an entirely reasonable thing to consider. ANY technology can fail, and your single card linked to a single account at a single bank is certainly no exception. It's not likely to happen - the banking system in general and most banks and most cards issued by them are very reliable. But stuff happens. Maybe the chip/mag stripe goes bad. Maybe they whip out their card to use it, and drop it - and it disappears down into a sewer grate. Maybe they just lose the card or have a wallet stolen. Maybe their bank at home suspects fraud and locks the card (this happened to me once, even though I had alerted the bank I would be traveling). Maybe that or something else happens on a Friday afternoon during a long holiday weekend. It's not hard to imagine ways that you could lose the use of the one card you were counting on for daily needs.

The problem is that single point of failure. The solution is simple: diversify that on which you depend.

I generally don't get beyond walking distance from my house without having at least 2 ways to get money. When I travel overseas, I always bring (and suggest the same to others) to have with you at least 2 credit cards and 2 ATM/Debit cards - per person (I pretty much always travel with my spouse). Furthermore, each of those cards should be associated with a separate account - because the failure point could be at the account end. Ideally, they should all connect to different banks, too - because banks can be crippled by technical issues (and banks can even fail, though that's admittedly very unlikely).

That's 4 cards, per person. Two credit cards (useful for most things), and two debit cards (critical for getting cash). If traveling as a couple, that gives you plenty of redundancy to cover every calamity short of simultaneous asteroid strikes on Delaware and North Dakota.

Of course:

• Some folks will balk at the idea of having that much redundancy. They would be right in saying that for most people going most places, you probably don't need that degree of backup. There are lots of ways to pay for things, and available workarounds in a pinch. You should do what's right for you.
• The critical thing (to me, at least) is to eliminate, or at least reduce, the "single points" where failure could derail your plans.
  
• You need to have such instruments set up well before it's time to head for the airport.
• Having at least 2 credit cards and 2 ATM/Debit cards (all pointing to separate accounts) seems like a reasonable minimum to me. YMMV.

David makes a very good point about a single point of failure. Two days ago, I had ATMs at two different banks (not just different locations) malfunciton. And that was at home. Think about that happening abroad. We always like to have some money on us. Once in Paris, four different credit cards would not work to pay for dinner. But we had enough cash on us, so we didn't have to wash the dishes. We were later told it was a satellite glitch. But who really knows? It happened, and may happen again. TGFC (thank God for cash).

A year or so ago someone reported here that the physical chip popped off his or her credit card. That's a problem I would never have anticipated.

Due to my long, sad history of leaving a trail of credit cards behind me, I travel (solo) with two ATM cards and three credit cards. Aside from my own carelessness, I've had to deal with an ATM card that just didn't work at the beginning of two different trips (due to credit union errors) and three ATM card-return failures (though I solved two of those problems myself).

Thank you all for so much helpful information.
Being the scattered traveler that I am, it makes sense to double up protection with my spouse with both ATM debit cards and credit cards on different banks. And I have to admit, I don't always trust technology or my skill level at dealing with it.
I personally never used the cash back feature at the grocery store but found it tempting. Never sure if it was treated somehow as a cash advance (not worth it to me) or just a nice convenience offered by the bank. I too only use my debit cards for debit cards for ATM withdrawals.
I definitely feel better prepared with the various answers provided.

Years ago, I too once had the chip physically pop off a credit card, as I was picking it up (honestly, I sometimes do give my cards a "workout," but nothing beyond their design expectations, I think...). The chip just came off and ended up in my hand as I fumbled with the card. I was not using it to make a purchase at the time, and it was not while overseas, so there was no drama, just a surprise. But yeah, things can happen, and weird stuff does happen.

I personally never used the cash back feature at the grocery store but found it tempting. Never sure if it was treated somehow as a cash advance (not worth it to me) or just a nice convenience offered by the bank...

It's a convenience sometimes offered by a store. The bank doesn't care.

You can only get cash with your purchase when paying with a DEBIT card, not a credit card.

Withdrawing money via a credit card would be a separate transaction (called a "cash advance"), because that comes with jaw-droppingly high interest rates (interest which starts accruing the moment you get that cash), unlike purchases which do not come with ANY interest (assuming you pay your bill on time).

Getting cash through a debit card withdrawal  (perfectly OK and useful), and getting cash through a credit card cash advance  (very expensive and generally to be avoided unless you REALLY need it, like only if I was on my way to a hospital or police station...) are very different things, and not to be confused/conflated.