Signature mismatch in PAN Card and Aadhar Card

A person's signature should be unique and it should be the same on all documents. You can't have different signatures on different documents. When you have to link your Aadhaar and Pan, if the signatures are not tallying some officers may object and you will get into the problem.
So I suggest you change the signature on your PAn card and keep the same as that of the Aadhaar card. Changing the signature on PAN can be done online or offline. It requires specific forms, documents and charges. You can do the same online by following the following steps.
Step 1:
Visit the NSDL official website (https://www.onlineservices.nsdl.com)
Select the option of "Changes or Correction in existing PAN Data' from the Application Type. Fill in the application with asked for details.
Step 2:
Complete KYC. The site will guide you on how to complete this. See the various options and select which will suit you.
Step 3.
Select 'Signature Mismatch'.
Provide details of your parents.
Provide your complete address.
For digital submission of the form and documents select 'Yes'.
Upload the documents and signature.
Submit the application.
Step 4: Make the payment as mentioned on the site and wait for the PAN card to be delivered.

Once you receive the new PAN Card you will not have the problem of signature mismatch.

Alternatively, you can change your signature on the Aadhar card also. You can visit your nearest Aadhar centre and the person there will guide you.

The Aadhaar card does not bear your signature.. Authentication based on Aadhaar card is based on bio metrics. So that verification is done by matching the fingerprints etc which your have given and recorded in your Adhaar card database. Hence you need not worry about the signature you have given for Aadhaar card. However you have to ensure that other details especially the name with spelling and spacing, and the address match with other documents .

PAN card bears name and address, photo and signature. So the PAN details have more parameters and you may ensure that they are correct and update. If they are all correct and there is some difference in Aadhaar card,then it is relatively easier to rectify in Aadhaar card. After correction you may also ensure that both are linked too.

As you have now doubts about the uniformity of your signatures, you may first visit your bank and give the latest signature with clarity after filling up the update KYC form. Then you may match and take up to update your PAN and other important documents with that specimen signature.

You may visit NSDL website for details in updating PAN details.

PAN card have more importance in respect of signature. Aadhar card's signature authenticity is based on biometric that means It is verified by fingerprint. So, no need to worry about it. If your PAN card having different signatures then it may create problems in future. So, there is a need to rectify it for which you will have to complete some formalities. At first, for making required corrections you should visit NSDL official website for PAN update. Here, you will find all details regarding PAN step by step. You have to fill the application form. After filling application form, you should submit the form along with the required documents and signature.
If you are eager to change your signature on the adhaar card also then visit the adhaar centre.

You need to maintain uniformity in respect of signatures in all your documents and the same thing is applicable for both Aadhar Card and PAN Card. Since your signature is not matching between the signature appearing on the Aadhar Card and the PAN Card, this needs to be resolved with your immediate rectification.
You have not indicated when your PAN Card was made. Anyway, you need to ensure that the signature appearing in the PAN Card is matching with the signature provided to your Bank - accounts. In case of mismatch, correct firstly the signature of the Bank - account with the fresh KYC formalities.
Then you have to go to NSDL site for updating your PAN Card with the latest signature with the fresh filling of the form appearing your signature at the end and finally submit the form along with latest photographs and prescribed fee. You will be issued a fresh PAN Card in lieu of the present one.
Finally you will have to approach the Aadhar Centre for the correction of your signature. You need to submit an application indicating your latest signature and request the authority for the correction.
In that way, mismatches can be eliminated from both Aadhar Card and PAN Card including your Bank Account.

As far as the Aadhar card is concerned, it identifies you as your identity through your fingerprint and retina of eyes, and for this, the signature, etc. information may be less important but the PAN card not has some kind of biometric identification. Therefore, it would be appropriate that you get your signature changed on the PAN card. For this, you have the following suggestions -

You can get the correction done online, for you can take the help of the https://www.onlineservices.nsdl.com website. After that you have to go to the application type, it will give you another option, going to this option you will have to click on Changes or Correction in existing PAN Data. After that, you will be asked for some details about yourself. Fill in these details.
When you will fill in these details then you have to enter the captcha. When all this is done then you have to click on submit. For verification, you will have to provide Aadhaar, passport, or other documents or upload them on the site. After this, you will be given the option to make a payment. When you make the payment, you will get a transaction number. After that, you will get a form. In that, you have to tell which PAN card mistake you want to get corrected. After filling in all this information you submit it. After about 15 days you will get your new PAN card along with the update.

If you want, you can also go to any cyber or related government office to get the PAN card updated, here you will be given only a form in which you will have to fill it with some information that you want to change your signature and at the same time You have to provide a document in which you have the same signature. After submitting the form, the further process is done by the people of the department and after a certain time, your updated PAN card will come to your permanent address.