Is there at least one country where travelers without residency rights require no proof of onward travel?
Yes there is; the United States, for travelers with visas (see below).
I'm mainly trying to figure out if evey single "Do I need a return ticket" question can be answered with a Yes.
No. As an example, travelers to the US with a visa are not required to show a return or onward ticket. (This is in contrast to the requirement for Visa Waiver Program travelers.)
As an example, a Nepalese citizen (not eligible for the Visa Waiver Program) traveling to the US from the UK yields the following; note the absence of any mention whatsoever of return or onward tickets:
/ 13APR17 / 1808 UTC
National Nepal (NP) /Destination USA (US)
- Passports issued to nationals of Nepal must be valid for the
period of intended stay.
- Authorization for Parole of an Alien into the United States
(Form I-512) must be valid on arrival. Passport Exemptions:
Visa required, except for Passengers with an Authorization for
Parole of an Alien into the United States (Form I-512). Visa
required, except for Those admitted to the USA on a visa, returning to
the USA after a visit of max. 30 days to Canada or Mexico or to
adjacent islands (except for Cuba) For details, click here . Holders
of F or J visas must For details, click here Minors:
- Children, up to/incl. 15 years of age, excluding nationals
of the USA and nationals entitled to travel under the US
Visa Waiver Program (V.W.P.), are allowed to travel on their
parent's passport. A person included in the passport of another may
not use the passport for travel unless he/she is accompanied by the
- Minors traveling unaccompanied, or accompanied by one parent or a person other than parent/legal guardian, For details, click here.
- A passenger may enter the USA with a valid visa in an expired passport, provided For details, click here
- Beginning students holding "F", "J" or "M" student/exchange visitor visas For details, click here
CHECK For details, click here - CHECK LATEST NEWS AND UPDATES ON