Turn the details of your own trip into a comparison you can inspect: the data you need, the days on which you will use it and the roaming product you are actually eligible to buy.
A seven-night holiday does not always create seven roaming charges. A pass may run on Irish calendar days, a bundle may start as soon as you buy it, and an included allowance may cover the whole trip. Enter what you know below; where a tariff detail is genuinely unknown, the calculator will say so instead of producing a reassuring but unreliable number.
Published 11 September 2026 · Editorially updated 12 September 2026 · Source checks last completed 11 September 2026 · Editorial image is illustrative · Commercial disclosure: suitcase.ie sells travel eSIMs.
Personalised scenario
Estimate your incremental USA data cost
No account or provider login is required. Your inputs remain in this browser and are not submitted to suitcase.ie.
How the estimate works
First, the calculator checks whether the selected option applies to your plan. It then uses any USA allowance you know is included before pricing whole passes or bundles. A spending limit may stop further use, so it is never treated as though it had bought the rest of the data you asked for.
For comparison, the current suitcase.ie USA plans are checked for both allowance and validity. The result shows the least expensive single plan that covers both; it does not automatically choose the largest or most prominent option.
Billing dates are not the same as holiday nights
A journey can cross more Irish billing dates than the number of hotel nights. In advanced mode, arrival and departure are interpreted in the selected US time zone and compared with Europe/Dublin. This matters because Ireland and the USA do not always change their clocks on the same weekend.
Vodafone Roam Extra starts at purchase and includes the purchase day. Three’s one-day pass uses Irish calendar days; its multi-day passes expire at 23:59 Irish time on the stated day and must be manually re-added if used again.
Before relying on the result
Check the linked provider evidence and your current plan terms. Prices and eligibility can change after the displayed review date.
Read the tariff comparison and methodology →Evidence
Sources
- Vodafone Ireland: Roaming rates and weekly data bundlesChecked 2026-09-11 · Eligibility and charging priority depend on the customer's plan. RED Roaming can take priority.
- Vodafone Ireland: Travelling abroad supportChecked 2026-09-11
- Three Ireland: Three Roaming Passes Billpay Add-onsChecked 2026-09-11 · Consumer bill-pay terms. Temporary 9GB and 21GB promotions expired on 26 August 2026 and are excluded.
- Three Ireland: Roaming guidanceChecked 2026-09-11
- eir: eir Mobile consumer bill-pay price list, part 12.2Checked 2026-09-11 · The published 1GB USA add-on does not establish validity, stacking or repeat purchases, so no 5GB eir scenario is accepted.
Tariffs, coverage and transport arrangements can change. Check the linked provider or operator source before relying on a time-sensitive detail. Material corrections are reflected on this page and in its evidence record.
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