letter of invitation
& Visa information
letter of invitation|Visa information
letter of invitation
It takes CLEO Management 7-14 days to process the letters of invitation.
Please fill out all required informationOnline Formas best you can.
Important information about Visa invitation letters (read):
- Your name must appear exactly as it appears on your passport. Any difference between the name on your passport and the name on your invitation letter or other documents may result in your visa being delayed and/or denied.
- If you are presenting a work please indicate the title and the session in which the work will be presented or, if you are exhibiting, indicate this in your application.
- Please note that each person requesting an invitation letter must fill out a separate form. All letters are sent in PDF format to the specified email address. If a paper letter is required, reply to the email. Requested paper letters will be sent free of charge by airmail. It may take a few weeks for this option to become available. If you want to expedite the process, you can send a letter through Federal Express with the recipient's Federal Express account number or credit card number and expiration date. Please also include your billing address in the inquiry email.
- CLEO Management reserves the right to request additional information about the assistant's company or affiliation to ensure the validity of the requests. Meeting attendees do not have to wait for their work to be accepted to apply for a visa invitation letter. CLEO is unable to contact US embassies to assist an individual attempting to attend a meeting.
- We recommend that you obtain your travel visa prior to registering for the conference as cancellations over the pre-registration threshold may incur a cancellation fee.
How to applyRequest a visa invitation letter
People who need letters of invitation to obtain a travel visa should apply with theOnline Form.
Do you have questions about the visa invitation letter application process?
Please contact us:einladungen@optica.orgÖ
CLEO Management - Letter of Invitation
2010 Massachusetts Avenue, NW
Washington, DC 20036
Visa information
- Apply for your visa now
- View Waiver Program
- Electronic travel authorization system
- Visa Application Guidelines
- arrange an interview
- Useful information to prepare for the interview
- Attend your visa interview
- Visa Renewals
- Web sources
Apply for your visa now
The visa application process for entry into the United States is subject to a greater degree of scrutiny than in the past. Because of this, the application process can take up to six months or longer.You must apply for your visa as soon as possible, but no later than three months before you travel to the United States.
Generally, a citizen of a foreign country wishing to travel to the United States must first apply for a visa, either a nonimmigrant temporary-stay visa or an immigrant permanent-stay visa. Visitor visas are nonimmigrant visas granted to individuals who wish to enter the United States temporarily for business (B-1 visa category), tourism, leisure, or visiting (B-2 visa category), or a combination of both. (B-1 /B-2).
The application for a visa takes place in several steps. The order of these steps and how they are performed may vary at the US Embassy or Consulate where you are applying. Consult the instructions available onUS Embassy or Consulate websitewhere do you want to apply
View Waiver Program
Full39 countrieswho participate in theView Waiver Program🇧🇷 If your country is on this list and you are traveling to the United States for tourism or business purposes for a maximum of 90 days with a valid passport that meets US requirements and the listed conditions do not apply to you, you do NOT need a visa . 🇧🇷 Otherwise, you will need to apply for a visa.
Electronic System for Travel Authorization (ESTA)
ESTA is an automated system that certifies visitors' eligibility to enter the United States under theVisa Waiver Program (VWP)🇧🇷 ESTA approval does not determine whether a traveler will be admitted to the United States. US Customs and Border Protection officials make eligibility determinations upon arrival of travelers. The ESTA application collects biographical information and answers VWP eligibility questions. ESTA applications can be submitted at any time prior to travel, although it is recommended that travelers apply as soon as they begin planning their trip or before purchasing airline tickets.
Please note that under the new changes, the following categories of travelers will no longer be eligible to travel to or be admitted to the United States under the Visa Waiver Program and will apply and go through the standard visa application and interview process must:
- Citizens of VWP countries who have traveled to or stayed in Iran, Iraq, North Korea, Sudan, Syria, Libya, Somalia and Yemen (with limited exceptions)
- Citizens of VWP countries who are also citizens of Iran, Iraq, North Korea, Sudan or Syria.
- request THAT
Visa Application Guidelines
Complete the online visa application
- Online Nonimmigrant Visa Application,Formular DS-160–Learn moreto complete the DS-160. You need to:
- 1) Complete the visa application online
- 2) Print out the confirmation page of the application form to bring with you to the interview.
- Photo– You submit your photo when you fill out Form DS-160 online. Your photo must be in the format explained inphotographic requirements.
arrange an interview
Face-to-face interviews can be critical to successfully and efficiently obtaining a visa to enter the United States.🇧🇷 One factor that contributes to the longer processing time is an in-person interview, which is now required as a standard part of visa processing for most applicants. Group interviews are not recommended. Applicants should be prepared to clearly state their intention to return from the US and to explain in detail how they will spend their time in the US. It's not enough to simply say, "I'm attending a meeting." Embassies are requesting more details, as well as documents and information supporting and proving these intentions.
Individuals are strongly advised to contact the embassy or consulatearrange a personal meetingas soon as it becomes known that a visa is required for entry. Please note that qualifying for a visa outside of your permanent place of residence can be difficult. Interview wait times vary by location, time of year, and visa category, so you must apply for your visa in advance.
Useful information to prepare for the interview
- A non-refundable fee will be charged.Visa Application Fee🇧🇷 Consult the instructions on the embassy or consulate website where you can request more information on how to pay the fee.
- Gather the required documents:
- passportValid for travel to the United States: Your passport must be valid for at least six months beyond your stay in the United States, unless country-specific regulations state otherwise. If your passport lists more than one person, each person who needs a visa must submit a separate application.
- applying for a nonimmigrant visa, Formular DS-160 confirmation page
- receipt of payment of the registration fee,whether you need to pay before your interview.
- Photo– You submit your photo when you fill out Form DS-160 online. If the photo upload fails, you must bring a printed photo in the format explained inphotographic requirements.
- Additional documents may be required to determine if you qualify. Additional documents requested may include, for example, evidence of:
- The purpose of your trip;
- Your intention to leave the United States after the trip;
- Your ability to pay all travel expenses.
- Evidence of your employment and/or family relationship may be sufficient to demonstrate the purpose of your trip and your intention to return to your country of origin. If you cannot pay for all of your travel expenses, you can show that someone else is paying for some or all of your travel expenses.
Use:Visa applicants must qualify based on the applicant's residency and connections abroad, and not on assurances from American family and friends. You do not need a letter of invitation or an affidavit to apply for a nonimmigrant tourist visa. If you choose to bring a letter of invitation or affidavit to your interview, remember that this is not one of the factors used to decide whether you will be issued or denied a nonimmigrant tourist visa.
Attend your visa interview
During your visa interview, a consular officer will determine if you are eligible to receive a visa and, if so, which visa category is appropriate based on the purpose of your trip. You must demonstrate that you meet the requirements of US law in order to be granted the visa category you are applying for. Inkless fingerprint scans are taken as part of the application process. These are usually recorded during the interview, but this varies by location. After your visa interview, your application may require additional administrative processing. The consular officer will inform you if this is necessary for the processing of your application. If your visa is approved, you may be able to pay a visa issuance fee and you will be informed of how your visa passport will be returned to you. Check theVisa processing timeto find out how quickly your passport with visa can usually be picked up or delivered by courier.
Visa Renewals
Whether you are applying for your visa for the first time or renewing it, use the same application process. Some applicants who wish to renew their visas under certain visa classes may qualify for the Interview Waiver Program (IWP), which allows eligible individuals to apply for a visa renewal without being interviewed in person by a U.S. consular officer. Check the instructions on the US Consulate's website.US Embassy or Consulatewhere you are applying to determine if the IWP is available and if you qualify.
Web sources
US Customs and Border Information
Frequently asked questions about the Visa Waiver Program
US Department of State Visa Information.
Department of Homeland Security
National Academies International Visitors Bureau
- CLEO management is unable to contact the US embassies to assist any person attempting to travel to the host country to attend the conference.
- If your visa is delayed or refused, please contact the consulate processing your application. TestVisa refusalfor detailed information on visa inadmissibility, denial and exemption.
Visitors are not permitted to accept employment or work in the United States.
Unless canceled or revoked, the visa is valid until its expiry date. Therefore, a valid US visa is still valid in an expired passport. If you have a valid visa in your expired passport, do not remove it from your expired passport. You can use your valid visa in your expired passport along with a new valid passport to travel and enter the United States.
(Video) How to Write an INVITATION LETTER for TOURIST VISA- For detailed information on how to apply for a visa, see the online resource links above.