Questions, questions...
 

In spite of the efforts of many to help understand the world of "prepaidgsm" and other providers, there are many of us who are still faced with a lot of questions.
After several days surfing the net, I discovered how insufficient the information are.
1- SIM cards: there are different types but nobody tells you which one goes into your phone and, if you are like me, you don't know what you device can take.
2- I have still not understood the time management of those cards, buying more time has several options and if I grasp the literature, if you call to buy there is a charge but if you go to a retailer it is free???
3- If all the time is not used while abroad, is the credit still available on a future trip?
There are still other questions that are not very clearly answered or not at all.
Every site is making great efforts to help consumers but the whole thing is getting pretty confusing for non experts like me.
Simplicity would be welcomed and surely as profitable.

I am sort of a newbie too so I understand your confusion. It will help to know which countries you are traveling to and what you need the sim card for then perhaps someone on here can help sort out some of your questions.

As far as I know there are only two usual types of SIMs. A regular and a micro SIM. Micro SIMs are not used very much on many devices. They're used on iPad and the new iPhone 4.

I'm not sure what you mean by "time management." All prepaid accounts have some requirement to keep the account active. You either have to add more minute vouchers by a certain date or you have to place a billable call by a certain date in order to keep the account active.

An account's validity is determined by the carrier's terms. Most have six months or a year's expiry on the accounts by which time you must add more minute vouchers in order to retain any balance in the account. Other carriers don't necessarily require any more vouchers but require that you place a billable call every six months (T-Mobile is one such carrier and is what's required in the UK and in the NL and perhaps other T-Mobile countries as well.

Any credit you have in your account will continue as long as you follow the carrier's procedure i.e. to add vouchers or make billable calls depending on what the carrier requires.

Sorry it's all a bit confusing. The first confusion you seem to have (about the size of the SIM), is a relatively recent development by Apple. As mentioned above, up until the iPad and iPhone4, every GSM device in the world had exactly the same SIM card (with few exceptions). As it is you also have to remember that you will not be able to just use another operators SIM in your existing phone unless your phone has been 'unlocked' in order to be able to do so. Also you will have to check that your phone's built in operating frequencies exist in the country you are visiting. If in doubt, just post a specific question here which states the Phone's model, current operator and the country you intend to visit.

In terms of the rest of your questions, they really are very specific to operators. There are thousands of operators in the world, and tens of thousands of prepaid tariffs. We couldn't possibly generalise about them all. This forum has been set up so that people from around the world can interact with each other and discuss developments etc. In most cases, somebody who is knowledgeable about a tariff (usually in their own country) can recommend a SIM for a newbie like yourself who might not have any idea what to get due to information overload. That is why the specific question on where you are going, and what useage you will be requiring was asked.
I have a question as well. I have often heard people from North America referring to credit as "time" and "minutes". Is this still the case these days? Isn't this dead confusing in it's own right? How can a system of credit that is based on time compensate for changes in tariff when you go to different countries? When I first went to the USA in 1996, I ended up working in some little Hicksville and initially had to rely on a few prepaid phone cards (not SIM's) in order to keep in touch with family back in Europe. However the problem I consistently found was that these cards were always advertised on their "minutes", which signified how many long distance (national) minutes I could speak for with my credit. In most cases, I could not ever find out how many international minutes I would get on my card, until I actually tried to make a call with them. On one "100 minute card" that our employer generously gave all of his international staff as a welcome gift, I was pretty surprised that it gave us under 5 minutes of talktime to most European landlines! Some of the other staff mentioned this to our boss later on, but he could just not understand why a "100 minute" card was just not what it said on the pack? I totally understand the confusion. He had paid just under $10 for each card, which placed the price per minute at over $2/minute. Later on, we managed to find cards that gave us close to 100 minutes to Europe for our 10 bucks! (10c/min). I guess he was frustrated that he didn't get us those in the first place! ;)

Anyhow, in the rest of the world, prepaid credit is generally referred to by its monetary value. (In Dollars, Euros, Pounds etc.). The tariffs that you will see here on prepaidgsm and any links that you will follow through will generally state various destinations as a cost per minute. (e.g. 3cents/minute to call from A to B, 15c/min to call from B to A).

This has to do with the expiration of the SIM. Generally, most prepaid SIM cards expire after a certain period of inactivity, or a certain time after the last addition of credit to the account. Sometimes this can be very generous (most British SIMs require just one billable action from anywhere at least every six months or one year to stay active), so as long as you are able to meet the provider's guidelines, the SIM will indeed be available for use on a later trip. Often the expiration date for being able to receive calls on the account will be longer than that for being able to place calls.

Note that pretty much everywhere outside North America, you do not pay to receive calls ever, unless you are roaming in another country.

Just to add something more from the other people.
All the "time" information is always written (when known) in the single operators' pages here on PrepaidGSM.net under the word "Validty". In the same cell are usually listed the different recharge vouchers too and their validity, credit, bonuses, etc...
There's not 1 single rule, there are hundreds of different rules depending on the Country, the operator, the tariff...
You just need the patience to read carefully the National Operators pages. Then if you still have doubts you can ask here.

Also note that just about everywhere else outside North America differentiates between mobile and land lines, when it comes to how much callers are charged. So, callers calling your mobile will pay a premium. For example, it's cost about 1 US cent (free on a lot of carriers) to call a UK landline. However, calls to a UK mobile is easily 18 US cents and above. So, whatever card you end up getting, your callers should be made aware of this.

Something else:
To 1: Except of the new Apple stuff mentioned almost all GSM-phones are using the same kind of Sim-cards. So these Sims fit in all phones. So there is almost never a problem. But you have to check which bands are needed in the country / in the countries you want to visit. Most networks are using the 900 MHz band and the 1800 MHz band (Europe, Australia, Asia, Africa) but in the Americas you will find (almost only) 850 MHz and 1900 MHz band networks. And there are a few UMTS-networks like "3" (UK, At, Dk, Se, Au..) and "Melita" (Mt) which do not use GSM but UMTS. The best thing is to have a quad-band phone (850 MHz, 900 MHz, 1800 MHz and 1900 MHz band) which will work almost everywhere.
To 2: As mentioned, usually you top up your account with a value of money. "Time" does not matter, because in most countries you do not pay for incoming calls while being on your home network. Because calls to mobiles are more expensive then to landlines, in most countries the terminating fee is higher on mobiles ("Calling party pays").
To 3: Not every provider is allowing roaming for prepaid customers, or only limited (T-Mobile US prepaid does not roam in an other T-Mobile country!). To keep your number alive, you should have the possibility to use the Sim!

SIM lifetime
 

I must admit, even though I am an experienced traveler, I too am confused about how these PAYG plans work. For example, I have a SIM from Vodafone Romania purchased 7/14/10. I have a permanent local address and the ability to top up locally or abroad. I have registered the SIM with the website, which tells me that I have 9,78 euro credit, valid until 11/11/10. It offers me the ability to top-up (4 euro valid 30 days, 10 euro valid 60 days, etc etc). I have roaming enabled, can use the SIM abroad, and APN settings let me use data as well.

Help me process this info clearly and please correct my misunderstandings...

1. If I do nothing, after 11/11/10 my SIM will not be capable of making outgoing calls, but will receive calls? If so, until when?
2. If I do nothing, after 11/11/10 my credit is lost? If so, now to recover?
3. If I top up prior to 11/11/10, the SIM is extended for just the newly purchased lifetime, or does the SIM itself get extended 10 months but the ability to initiate calls extends only 30 days, 60 days, etc? this relates to the National Operators web page which uses notation like "4+10 months", which I don't understand.
4. Is topping up considered an activity which gives life to the SIM, or must there be a billable event like a phone call or text message?

ultimately, what must I do prior to 11/11/10 in order for me to keep the same number until I return in the summer of 2011?

Thanks!

Someone will correct me if I'm wrong, but with prepaid any balance of money in your account will remain as long as you refill with additional funds or for some carriers you need to make something billable (such as a call or a SMS) to extend the account further. As to your question number 4 I'm not sure whether topping up is considered an action, but my guess is that it does. I'd contact the carrier to be sure, but I'd think that the action of topping up would be sufficient.

Vodafone Ro is (compared to other providers) easy to handle:
- With *123# (Send) you may check the actual status (the expiry date)
- When reaching the expiry date your account gets frozen (hybernation)
- You may not use any services, you have to pay for
- You may receive SMS
- You may receive calls (when hooked up to Vodafone Ro - not while roaming!)
- With *123# (send) you get the information, how much credit is frozen and the last date, you may recharge your account
- Maximum time is 300 days
- After recharing all the money (the "new" one and the "frozen" one) may be used again
- The (new) expiry date depends on how much you toped up
- When active: I think, the new validity date will not extend the old validity date anymore (here I am not completly sure)
- See https://www.vodafone.ro/personal/car.../index.htm#id2 and then click on "Click aici pentru detalii despre valorile de reincarcare si valabilitate".
In your case:
Expiry date (Begin of Hybernation): 10.11.11 (11th of November 2010)
Last date before closing your line: 11.09.06 (6th of September 2011)
So: If you want to use your number (active) you have to recharge it before 11th of November.
In this case, the new expiry date will be:
- The old one, if the time extension is shorter than the "time" you would get
- The time corresponding to your recharge value in all other cases
Examples: You would recharge on 10.10.10 with 5€: Your expiry date would not change (it would still be valid for 31 days, the new one would be only for 30 days).
You would recharge on 10.11.10 with 7€. Your expiry date would be 11.01.09 (60 days)
If you 're doing nothing: To avoid loosing your money and your number you have to recharge before 6th of September 2011.

re: SIM lifetime
 

Schlips1,

thanks for the very helpful answer. some follow up questions:

if the SIM is extended only according to the top up amount, it seems useless to keep a SIM since I cannot justify topping up and extending the card if I am not in the country to use it on the local network. for example, it would cost too much to keep topping up every 30 or 60 days from Nov 2010 until summer 2011. i would never be able to consume that much credit that i would accumulate.

what is the behavior of the SIM between the 4-month validity and the 10-month (300-day) expiry date? it seems the least expensive way to keep a number in perpetuity is to wait until the 300-days is approaching, but by that time, the SIM cannot be used outbound unless it is topped up right? and in this case, the small top up amounts only get me a short extension.

i'm still not clear about the best strategic time to top up if i want the same phone number for the summer 2011: prior to Nov 11 2010 (top up while abroad), or July 2011 when i actually arrive on the local network? or is there another option: to invoke a billable event prior to nov 11 2010 and do not top up at all if i am content with my credit level?

thanks again for your help.

(feel free to write privately if this is already clear to everyone else)

Just top it up, when you want to use it! The money will not get lost during hybernation! In most cases it does not make sense to keep it active (for outgoing calls). But you may use it in hybernation (eg. in the USA) to receive SMS. Because they are free!

Yes, that's it. But do not forget to top up!

I would do it while roaming before you are leaving. So you may use it when you 'll arrive (especially in a case of emergency).

clear explanation of PAYG terms
 

Here is quite probably the clearest explanation that I have read regarding the conceptual terms of PAYG SIMs as it relates to the SIM's active and dormant lifetimes, and a link to a top-up website for smaller markets (ezetop.com) which I had never heard of. I realize most here understood the finer nuances but this paragraph made it very clear for me and I feel better equipped to strategically keep my SIMs around in light of my various travel plans. It comes by way of Vodafone Romania

Each time you recharge your Prepaid Card, you receive 1 to 5 validity months to use your credit, depending on the recharged value. After the validity period expires, you will benefit from an extended period of 10 months (300 days) in which you can be called. You can recharge the prepaid card anytime through any of these methods:

Online from MyVodafone – you can log in your Vodafone account, top-up your prepaid card and pay with credit card from any place in the world.

With value cards
Electronic recharge
International recharge - through www.ezetop.com
Call *122# and find prepaid services created to help you keep in touch with friends and family outside Romania.